Open questions

Where sources disagree, MineArchive keeps both accounts rather than picking one; where a fact could not be settled, the record says so. This page collects every such claim across the archive: 1230 in all, marked (disputed) where two sources say different things and (uncertain) where the sources read leave it open. Each links to the record, where the claim sits beside the sources it rests on. If you can settle one, the About page says how to get in touch.

Mines

Aberaman Colliery Rhondda Cynon Taf

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Aberaman' (catalogue SWR1244, Nine Feet, dated 1957); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Abercrave Colliery Powys

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Abercrave' (catalogue SW204, Two Feet., dated 1953); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Abercwmboi Colliery Rhondda Cynon Taf

• Ray Lawrence gives the sinking as 1856 to 1,027 ft 7 in to the Four Feet seam, 66 inches thick, and notes an Abercwmboy colliery working in 1828 under a Mr Davies. (disputed)

Abercynon Colliery Rhondda Cynon Taf

• Abercynon was linked to the Lady Windsor Colliery and the two worked as a single unit; Welsh Coal Mines dates the link to 1973 at a cost of £450,000, while Wikipedia gives 1975. (disputed)

Aberllefenni Slate Quarry Gwynedd

• Aberllefenni is reputed to be the longest continually operated slate mine in the world, closing in 2003. (uncertain)
• The quarry employed around 190 men at its peak around 1890, falling to around 40 by 1950 and just 3 at closure in 2003. (uncertain)

Abernant Colliery Neath Port Talbot

• In September 2011 Waste Recycling Group submitted plans for an anaerobic digestion facility on the old colliery site. (uncertain)
• Mining Remediation Authority catalogue lists plans under ABERNANT COLLIERY, including tip plan SWT3859 (spoil tip no. 276, dated 1968). (uncertain)

Acomb Colliery Northumberland

• The museum's returns show a peak of 316 employed in 1940. (disputed)
• The memorial plaque says the colliery employed 290 men at its peak. (disputed)
• The plaque says the colliery produced over 70,000 tons of coal a year. (uncertain)

Adelaide Mine Cheshire

• Given as roughly nine and a half acres of workings at a depth of around 330 feet. (disputed)
• Given as around fifteen acres by 1896, with rock-salt pillars around ten yards square spaced twenty to twenty-five yards apart, worked under manager Thomas Ward. (disputed)

Alderley Edge Mines Cheshire

• A May 2013 permission-visit report describes Wood Mine's original entrance being blasted shut in 1964 after accidents involving ill-equipped visitors, before the Derbyshire Caving Club reopened it in 1970 with National Trust permission; the passages retain green-coloured water features from copper mineralisation. (uncertain)
• The mines are recorded as having seen numerous accidents and six fatalities after they were closed, the entrances having been left unbarred. Accidents are reported to have stopped after the Derbyshire Caving Club took on the lease in 1969. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Alderley Edge' (catalogue OM882, Copper Ore, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Alexandra Quarry Gwynedd

• Eight men were killed at the quarry between 1895 and 1913; in 1907 a locomotive boiler explosion on the quarry tramway killed one passenger and severely scalded the driver, resulting in £50 fines for both the agent and the company. (uncertain)

Alfreton Colliery Derbyshire

• The Buddlepit mine database gives Alfreton as sunk in 1886 and worked from 1895 to 1968, which sits a little oddly against the museum's returns showing 639 people employed in 1894. The likeliest reading is that the two are counting different things — a sinking that began in 1886 and full production from 1895 — but no source read says so. (uncertain)

Allington Quarry Kent

• In the region of twenty million tonnes of stone were extracted from the quarry, for local buildings, roads and railways, most recently for the Channel Tunnel Rail Link. (uncertain)
• There is evidence of quarrying in the area from 1174, when Allington Castle was built, and the quarry itself had certainly existed since the 1790s. (uncertain)
• In 2001 Hanson Aggregates decided to close the site and relocate to Blaise Farm near Offham, estimated to hold thirty-five million tonnes of reserves. (uncertain)
• Only two ragstone quarries now operate in Kent: Hermitage Quarry at Barming, the sole supplier of Kentish ragstone building stone, and Blaise Farm, worked mainly for aggregate. (uncertain)

Alloa Colliery Clackmannanshire

• Local accounts of the company give Whinhall Pit No. 3 as started in 1902 and closed in 1919, and Jellyholm as started in 1887 and closed in 1921 when it became unprofitable. Neither date comes from the official returns, which show both pits still returning coal in 1920. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Alloa' (catalogue 11913, Coal Mosie, dated 1936); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Alvecote Colliery Warwickshire

• No magistrates' cases have been found against Alvecote mineworkers, unlike the pits around Nuneaton and Bedworth; the colliery's men are thought either to have been more loosely disciplined or to have refused to join the Warwickshire Miners' Association, and they worked through the 1912 strike. (uncertain)

Amington Colliery Staffordshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Amington' (catalogue 2058, Ryder (Bel Smithy) And Ironstone, dated 1886); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Annandale Colliery East Ayrshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Annandale' (catalogue S1336, Major, dated 1919); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Annesley Colliery Nottinghamshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Annesley' (catalogue EM1211, Deep Soft, dated 1983); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Ansley Hall Colliery Warwickshire

• Our Warwickshire’s article on this colliery has it scheduled for phased closure in 1959; its article on Haunchwood says Ansley Hall closed for production in 1964, when two of its underground districts were assigned to Haunchwood. (disputed)

Ashton's Field Colliery Greater Manchester

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Ashtons Field' (catalogue SFE250, Surface, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Auchengeich Colliery North Lanarkshire

• The colliery is recorded as having been owned by James Nimmo and Company before nationalisation. (uncertain)

Auchlochan Colliery South Lanarkshire

• Hugh S. Dunn operated Auchlochan from 1893 to 1902, before W.C.S./C.S. Cunningham; a specialist railway-history source sequences Dunn then Cunningham then Caprington & Auchlochan Collieries without giving Cunningham's own start year precisely, which is not fully reconciled against this record's existing 1890-1900 Cunningham dates. (disputed)
• Caprington & Auchlochan Collieries Ltd removed the pumps from Auchlochan's lower levels in June 1931 as uneconomical, went into liquidation in 1932, and was carried on by liquidator A.S. Macharg with mining agent David Todd -- reports vary on the workforce during this period, between around 400 (normally employed at the pits) and around 800 (across the wider Coalburn district) -- before William Dixon Ltd bought the Auchlochan pits in 1934. (disputed)
• Auchlochan employed around 500 men at its 1968 closure, per a local-history account. (uncertain)

Auldhouseburn Colliery East Ayrshire

• The pit was about 25 fathoms deep and worked stoop and room in a seam of about seven feet, made up of a three-foot cannel coal and a four-foot ordinary coal separated by stone. A shaft depth of 32 fathoms is recorded in the 1873 fatality of Charles Clark, and the 1910 List of Mines names the seams as Nine Feet and Seven Feet. (uncertain)

Awsworth Colliery Nottinghamshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Awsworth' (catalogue 3924, Furnace Or Tupton, Three Quarters Or Tupton Three Quarters, Blackshale Or Silkstone & Kilburn, dated 1899); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Aysdalegate Mine North Yorkshire

• Buddlepit gives the mine as worked from 1863 to 1902; the Wikipedia table of Cleveland mines gives 1863 to 1880 at NZ652149 and notes that it later became part of the Spawood Mine as ventilation shafts. (disputed)

Backworth Colliery Tyne and Wear

• The Tyne and Wear HER describes the Algernon Pit as opened about 1820 as a pumping shaft of the Shiremoor Coal Company, with a beam engine erected in 1875; the Durham Mining Museum dates its sinking to 1853. (disputed)
• Eccles, Backworth's last pit, was the deepest in the Northumberland coalfield at 1,440 feet, and closed in 1980 after 165 years of mining in the area. (uncertain)
• As late as 1950, 2,905 people were employed in the collieries in and immediately around Backworth. (uncertain)
• Returns from 1883 onward record fireclay raised alongside the coal, and brickmaking was carried on north of the village on the site of the former C Pit from the late nineteenth to the mid-twentieth century. (uncertain)
• In the early 1970s Backworth Colliery's railway was one of the few places in Britain where steam locomotives could still be seen at work; several have since been preserved. (uncertain)

Bagworth Colliery Leicestershire

• Wikipedia records that the then Viscount Maynard had the first shaft of Bagworth Colliery sunk in 1828, with the coal at first carried to Leicester by road; the Northern Mine Research Society dates the instigation of the sinking by Maynard to 1826. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Bagworth' (catalogue EM836, Lower Main, dated 1964); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Ballochmyle Colliery East Ayrshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Ballochmyle' (catalogue 3885, Ell And Main, dated 1898); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Bankend Colliery South Lanarkshire

• A record from 1890 names the 'Owners of Chapelhall Colliery' as proprietors of a Bankend No.11 Colliery. (uncertain)

Bankton Colliery East Lothian

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Bankton' (catalogue 11914, Four Feet, dated 1933); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Barnsley Main Colliery South Yorkshire

• The Dearne heritage account instead says Barnsley Main originated as the Oaks Colliery, sunk west of Oaks Lane at Stairfoot in 1824, whose shafts were infilled after the 1866 explosions and replaced by new shafts at Ardsley opening as the New Oaks Colliery in 1870. (disputed)
• The Dearne heritage account says a 25 million pound refurbishment reopened the colliery in the 1970s and that the surviving headgear and two-storey brick engine house date from that work; the list entry dates them to about 1900 and 1956 and describes the 1970s use as man-riding, with the coal wound at Barrow Colliery. (disputed)
• The list entry says 361 miners and 27 rescuers died in the 1866 explosions at the Oaks; the Dearne heritage account gives 383 killed; this archive's own disaster record gives 361 as the official total and states that figure already includes 27 colliery employees and 23 volunteer rescuers. (disputed)

Baron's Quay Mine Cheshire

• The four-mine stabilisation programme is variously reported as costing around £28 million or around £32 million across different sources; neither figure is treated here as more reliable than the other. (disputed)

Barrow Colliery, Bryncethin Bridgend

• Small-scale house-coal working at Bryncethin — Robert Watson's pits in the 1830s and a small colliery at Tynycoed sunk c.1830 — predates the deep Barrow shafts by decades. (uncertain)

Bates Colliery Northumberland

• The colliery employed 2,000 men at its height, reduced to 1,700, then 1,400, and by agreement with the NCB to about 880 by early 1986. In May 1985 it was described in the Commons as employing over 1,700 men. (disputed)

Bathville Colliery West Lothian

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Bathville' (catalogue S3734, Main, dated 1892); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Bayton Colliery Worcestershire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Bayton' (catalogue 8022, Hard, dated 1923); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Bearpark Colliery County Durham

• Theodore Fry was involved in founding the Bearpark Coal and Coke Company in 1872, which established the coal mine at Bearpark. (uncertain)
• Bearpark Community Centre, a red brick building originally put up in 1921 as a miners' welfare hall, stands at the hub of the village with an old pit wheel in front of it as a memorial to Bearpark's mining history. (uncertain)

Beaufort Iron Works Blaenau Gwent

• The works and pits were sold to the Nantyglo & Blaina Iron and Coal Company for £300,000 in 1871 and closed within a few years; 1873 and 1877 are both given, while a separate account has the works closing soon after Partridge's death in 1862. (disputed)

Bebside Colliery Northumberland

• Bebside was formerly a mining village west of Blyth, a township in Horton parish and from 1866 a civil parish of its own until it was absorbed into Blyth in 1920. Its mine operated between 1858 and 1926, and it was served by Bebside railway station from 1850 to 1964. (uncertain)

Bedford Colliery Greater Manchester

• The account of the disaster states that the colliery was 'sunk in 1884', which conflicts with the 1874 start and 1876 first coal given in the fuller history of the colliery; no source read reconciles the two. (disputed)

Bedwellty Pits Blaenau Gwent

• An explosion at the No. 1 pit on 16 June 1865 killed twenty-seven miners, six of them boys under the age of sixteen. (uncertain)
• A further explosion on 10 March 1880 killed six men: Thomas Ball, 34; John Williams, 27; Thomas John Roberts, 27; Robert Cooper, 23; Charles Pugh, 19; and Henry Anthony, 29. (uncertain)
• The Tredegar Iron Company was created in 1800 by Samuel Homfray with Richard Fothergill and Matthew Monkhouse on a lease from the Tredegar Estate. It ceased producing iron in 1891 but continued to develop coal mines and work pits until nationalisation in 1946. (uncertain)

Beech Tree Colliery West Midlands

• Local tradition held that a manager from a neighbouring colliery bribed the Beech Tree nightwatchman for underground access, discovered a good coal seam running in one direction, and his own company then bought up the mineral rights on that side — presented in the source as contemporary rumour, not an established fact. (uncertain)

Beer Quarry Caves Devon

• A 2018 report on the neighbouring Hanson Aggregates quarry — a separate, later working opposite the historic show caves — describes an extensive underground tunnel network and notes that illegal raves around 2009-10 led the operator to install motion-sensor alarms. (uncertain)

Beezy Mine North Yorkshire

• Beezy Mine, Askrigg, appears in the Lists of Mines for 1863 to 1874. (uncertain)

Belmont Mine North Yorkshire

• The Durham Mining Museum gives the mine as closed in 1933; Buddlepit records Dorman, Long & Co. holding it from 1929 to 1933 and the mine as worked from 1853 to 1929; and a site account gives the second working as 1907-1931 with no ore extracted after 1921. (disputed)

Benbain Colliery East Ayrshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Benbain' (catalogue 7951, Sloanston, High, Splint And Low, dated 1924); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Benhar Colliery West Lothian

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Benhar' (catalogue S412, Ball, dated 1962); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Betteshanger Colliery Kent

• A miner named Cephas was killed in 1934 when a lump of loosened rock fell and crushed him while hewing coal, one of a number of individual fatal accidents recorded at the colliery. (uncertain)

Bideford Black Mine Devon

• Sources disagree on the closing year: 1969 is given by the Open University Geological Society report, the GooseyGoo site record and Kisin’s 2024 article, while the Story of Bideford Black project and accounts drawing on it give 1968. (disputed)

Big Pit Torfaen

• Sources disagree on some detail of the shaft's early history. The Blaenavon World Heritage Site's own account and welshcoalmines.co.uk both describe the elliptical shaft itself as the former Kearsley's Pit, sunk in 1860 and later deepened to reach the Old Coal seam at 293 feet (dated 1878 by welshcoalmines.co.uk, 1880 by the Blaenavon World Heritage Site and by Coflein, the Royal Commission's monuments record for Wales). The Northern Mine Research Society's more technical listing instead treats Kearsley's Pit — sunk c.1800, 5 feet in diameter — as a separate, older shaft from the elliptical Nos.1 and 2 Pits sunk 1860–1863, of which No.1 was the 18 by 13 foot shaft that became known as Big Pit. (disputed)

Birchenwood Colliery Staffordshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Birchenwood' (catalogue 9910, Ten Feet, dated 1929); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Birchrock Colliery Swansea

• Birchrock was opened in 1868. (disputed)
• National Coal Board records gave 1873 for the opening and the Inspector's report on the 1909 explosion gave 1869. (disputed)
• Welsh Coal Mines has the mine unlisted in 1881 and abandoned in 1882, reappearing from 1886; the NMRS has Cory, Yeo and Company working it with Graigola in 1882 and 1884. (disputed)

Birley Collieries South Yorkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Birley' (catalogue 5312, Silkstone, dated 1908); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Black Vein Colliery Caerphilly

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Black Vein' (catalogue SWT2914, Spoil Tip, dated 1984); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Blackcraig Lead Mines Dumfries and Galloway

• Historical accounts from 1904 refer to older, undated horizontal workings known as ‘old men’ in the area, pre-dating the Craigtown Mining Company's own shafts; Historic Environment Scotland notes there is no actual evidence of Roman-period mining at the site despite the Old Military Road's route following an earlier Roman road, so the age and origin of these older workings remains unconfirmed. (uncertain)

Blackett Level Northumberland

• The list entry dates the portal to 1854; the Blackett family history says construction began in 1855. (disputed)

Blackhall Colliery County Durham

• Wikipedia's account states that the first coal was drawn in 1913, a year earlier than the Durham Mining Museum's own 1914 commencement date. (disputed)
• The blackened beach was used for the climactic chase in Get Carter (1971) and, according to a 2023 account of the site's recovery, also as a location for Alien 3. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Blackhall' (catalogue D1360, Hutton 'L', dated 1974); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Blackrod Colliery Greater Manchester

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Blackrod' (catalogue 12606, Ravine Tops, Ravine Bottoms, dated 1939); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Blaen Rhas Colliery Merthyr Tydfil

• A separate account of the wider Dowlais Collieries group describes Blaen Rhas as worked for coal and fireclay, closing in November 1901. (disputed)
• J. Edwards, 28, a collier, died in a roof fall "at Blaen Rhos" on 14 June 1875 — very likely this colliery under a variant spelling. (uncertain)

Blaenau Saron Colliery Carmarthenshire

• Welsh Coal Mines' fatalities register independently records the same death — Thomas Davies, 23, collier, killed on 7 May 1879 by falling under trams on an underground incline at Llandybie — but attributes it to "Glynea Colliery" rather than Blaenau Saron; the identical name, age, date, cause and village make it very likely the same event under a differently recorded colliery name. (disputed)

Blaenclydach Colliery Rhondda Cynon Taf

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Blaenclydach Level' (catalogue SWR1357, No.2 Rhondda, dated 1903); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Blaengwawr Colliery Rhondda Cynon Taf

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Blaengwawr' (catalogue 10846, Graig, dated 1931); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Blaenhirwaun Colliery Carmarthenshire

• The Durham Mining Museum records six lives lost. Welsh Coal Mines records five — John Davies, Norris Howells, Thomas Richard Morris and William Henry Richards killed in the initial blast and David Pennington dead some weeks later of severe burns — with thirteen others injured and some badly burnt. (disputed)

Blagill Mine Cumbria

• The Buddlepit database's own summary states the mine was worked until 1905, while its narrative text states no production is recorded after 1895 -- a discrepancy not resolved within this pass. (uncertain)

Blairmuckhill Colliery North Lanarkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Blairmuckhill' (catalogue 11348, Ball, dated 1934); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Blantyreferme Colliery South Lanarkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Blantyreferme' (catalogue S430, Virgin, dated 1947); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Blue John Cavern Derbyshire

• The first documentary reference to Blue John is a 1766 mining lease mentioning 'ye Blue John, Castleton'; a popular tradition crediting Roman lead miners with its discovery is often repeated but is not supported by direct evidence. (disputed)

Boaterby Mine Cumbria

• John Messenger, a labourer of 50, was killed at Boaterby on 9 August 1879 by a fall of earth — six years before the quarry is recorded as going into production, which suggests work on the site began earlier than the 1885 date. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Boaterby' (catalogue OM7192, Gypsum, dated 1921); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Bodyst Uchaf Colliery Carmarthenshire

• An independent local account of the same 1890 episode names the site Bodyst Isaf rather than Bodyst Uchaf, but otherwise matches in every particular: Henry Herbert sank the mine in 1890, sold it to a Lancashire syndicate trading as the Ammanford Colliery Company Ltd (£40,000 share capital), who closed it and opened a new slant on Glyn-cywrch Farm land, working the same Red Vein seam, known as Ammanford No.1 Colliery or "Top Works". (disputed)

Boldon Colliery Tyne and Wear

• Other accounts state the pit was sunk by the Harton Coal Company in 1866, the winning commencing to sink to the Hutton Seam on 19 March 1866, with coal produced from 1869. The Durham Mining Museum gives the same day and month but 1869. The two cannot both be right. (disputed)

Bonawe Iron Furnace Argyll and Bute

• Historic Environment Scotland and Wikipedia give the closure date as 1876; Canmore's record separately states the furnace was finally closed down in 1874. Both figures are recorded rather than reconciled. (disputed)

Bonville's Court Colliery Pembrokeshire

• Welsh Coal Mines dates the opening to 1842 under the Myers Mining Co.; the Durham Mining Museum gives 1855. (disputed)

Boosbeck Mine North Yorkshire

• Two shafts were sunk to 288 feet in 1872 under a lease held by Stevenson, Jaques and Company; the Durham Mining Museum gives the opening as 1873, the year the mine first appears in the Lists of Mines. (disputed)
• Production ended and the mine was abandoned in March 1887 after a water feeder struck in February 1886 flooded parts of the workings; the Durham Mining Museum records the closure as 1886. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Boosbeck' (catalogue OM2372, Ironstone, dated 1887); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Booze Mine North Yorkshire

• A local legend describes a flood that killed 24 miners and 2 pit ponies after miners broke into an underground lake near Boldershaw, but researchers have found no record of this in parish registers; a smaller, unconfirmed accident killing three miners has been suggested as the story's possible real origin. (disputed)

Borrowdale Colliery, Brough Cumbria

• An undated Herald report describes a half-mile main level with horse-drawn tubs and eight men working by candlelight; the Old Cumbria Gazetteer, which quotes it, dates it only to the 1900s. (uncertain)

Botallack Mine Cornwall

• The mine is generally described as closing in 1895 on falling tin and copper prices; some secondary accounts instead describe operations continuing in reduced form to 1914. (disputed)
• Prince Arthur descended the Boscawen Diagonal Shaft on 15 May 1862 and the Prince and Princess of Wales in 1865, in the same gig involved in the 1863 accident; R. M. Ballantyne visited in 1868 and drew on it for his novel Deep Down. (uncertain)
• At its height under Stephen Harvey James's ownership the mine employed over 550 people, 340 of them underground. (uncertain)

Boundary Level Neath Port Talbot

• A local historian familiar with the district's old Ordnance Survey mapping has identified Boundary Level as "another Bevan and Bowen enterprise" — the same partnership documented as owning the neighbouring Upper Graigola Colliery between 1908 and 1918 — though no source gives a specific date for Bevan and Bowen's ownership of Boundary Level itself, roughly two decades before its 1891 abandonment. (uncertain)

Brackley Colliery Greater Manchester

• The Bridgewater Trustees developed Brackley Colliery in 1878 according to Engole's history of the Bridgewater collieries, and in 1879 according to the Northern Mine Research Society and Grace's Guide; the 1879 date also attaches to the installation of the No. 1 winding engine and headgear. (disputed)

Braichgoch Slate Mine Gwynedd

• The Corris Mine Explorers history dates the Braich Goch Slate Quarry Company to 1864, while Wikipedia's account has the Birley family establishing Braich Goch Slate Quarry Ltd on purchasing the lease in 1859. (disputed)

Braysdown Colliery Somerset

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Braysdown' (catalogue SWR258, Top Little Vein & Radstock Group, dated 1910); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Brayton Domain Colliery Cumbria

• The colliery village of Harriston at Aspatria was built to serve the mine and named after Joseph Harris, its owner. (uncertain)

Brereton Colliery Staffordshire

• Writing in 1957 the Victoria County History recorded that much of the coal had been worked out but that production was expected to continue for about fifteen years. The colliery in fact closed in July 1960. (disputed)

Brettell Lane Colliery West Midlands

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Brettell Lane' (catalogue WM545, Fireclay Thick Brooch Ironstone Ten Feet, dated 1912); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Bridgeness Colliery Falkirk

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Bridgeness' (catalogue 12910, Six Feet, Main & Smithy, dated 1941); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Brightling and Mountfield Gypsum Mines East Sussex

• Mountfield Mine closed in the early 1990s with its reserves virtually exhausted, having latterly used a heavy media separation plant to work anhydrite-contaminated gypsum. (disputed)
• Mountfield Mine is reported to have closed in 1998. (disputed)
• Brightling is reported as accessed by a 420 m drift at a 1:8 decline, with working depths from about 100 m to 350 m. (uncertain)

Britannia Colliery, Pengam Caerphilly

• The shafts were sunk from February 1911 to September 1913, and coal raising began early in 1915. (disputed)
• Sinking began in 1910 and the first coal was produced in 1912. (disputed)
• The North Pit was sunk to 2,181 ft 3 in and No. 2 Pit to 2,202 ft, to the Lower Nine-Feet seam. (disputed)
• Shaft No. 1 (downcast) was 615 yards and No. 2 (upcast) 714 yards deep. (disputed)
• Each winder had two 2,000 hp motors, either able to run it alone. (disputed)
• Each winder had two 1,600 hp DC motors, 3,200 hp in all, fed by Ilgner sets. (disputed)
• The colliery closed as a production unit on 8 December 1983. (disputed)
• Coflein gives 1989 as the colliery's closure, the year its pumping for Oakdale ended. (disputed)
• Coflein records the headframes and major surface buildings as remaining intact. (disputed)
• A 1987 photograph's caption describes the colliery as 'now long gone'. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Britannia Pengam' (catalogue SWR573, Brithdir, dated 1962); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Brodsworth Colliery South Yorkshire

• The Barnsley seam, up to 9 feet thick, was reached in 1907. Wikipedia gives the depth as 595 yards; the Northern Mine Research Society gives 541 metres — the two figures are close but not identical and are recorded here as separate accounts rather than reconciled. (disputed)

Broughton Colliery Wrexham

• Welsh Coal Mines states that Broughton Hall, the old colliery, closed in 1978 — a date that would make a pit sunk in 1835 one of the longest-worked in the Denbighshire coalfield, and which nothing else read confirms. (uncertain)

Broxtowe Colliery Nottinghamshire

• Mining Remediation Authority abandonment plans titled 'Broxtowe' are dated 1904 (Deep Hard), 1919 (Top Hard, catalogue 6897) and 1949 (Deep Hard), and Babbington's 1971 plan includes workings from Broxtowe; none is dated to the recorded 1929 closure. (uncertain)

Brymbo Colliery Wrexham

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Brymbo' (catalogue 6286, Drowsall, Powell & Queen (Wall & Bench), dated 1914); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Brynamman Colliery Carmarthenshire

• After a new entrance in 1894 it may have become Ynysdawella; leased to Edward Lange 1900-05; worked as Ynysamman by the Ynys Amman Colliery Co 1909-14. (uncertain)

Bryndu Colliery Bridgend

• Welsh Coal Mines dates the explosion that killed four to Thursday 11 November 1852; NMRS gives 18 November 1852. (disputed)
• Welsh Coal Mines gives twelve killed on 28 May 1858 and names twelve; NMRS gives eleven on 27 May. (disputed)
• By 1908 Bryndu had closed, with 461 employed at Cefn. (disputed)
• The colliery closed in 1913 after accumulated losses of £90,000. (disputed)
• Cefn Slip Colliery, opened about 1857 to supply the Cefn ironworks, became the Bryndu Colliery Co. Ltd in 1908 and closed in 1912 after serious water incursion. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Bryndu' (catalogue SWR1183, Red Vein (North Fawr), dated 1874); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Bryngwiog Lead Mine Flintshire

• Sixteen men perished when water from old workings flooded the mine on Saturday 22 February 1862. (uncertain)
• The dead were drawn from villages across Halkyn Mountain — Moel-y-Crio, Lixwm, Rhewl, Rhesycae, Foel, Llaneurgain and Cilcen among them. (uncertain)
• The villages around the mine have a lead-mining history of centuries; several buildings in the Wern-y-Gaer area of Rhosesmor are more than three hundred years old. (uncertain)

Brynhenllys Colliery Powys

• The Waunlwyd slant, part of Brynhenllys Colliery, was claimed to be the first colliery in the South Wales coalfield to have a stay-down strike, in October 1934, when twenty-four men stayed down for six and a half hours. (uncertain)

Brynmally Colliery Wrexham

• The colliery was probably sunk in the late 1830s or early 1840s and was purchased by Thomas Clayton and Company in 1849. It also went by the name Pwll y Pendwll. (uncertain)
• Water broke into the No. 3 pit on Tuesday 30 September 1856 and thirteen men lost their lives; the first body was not recovered until 26 October. (uncertain)
• An explosion on 13 March 1889 killed twenty men and boys. The cause was blamed on a fall bringing down an outburst of firedamp which was ignited by a naked flame. (uncertain)
• Several of those killed in 1889 were children: James Davies, a waggoner, was fourteen; Thomas Davies, a pony driver, sixteen; Edward W. Edwards, a waggoner, fourteen. (uncertain)

Buckhill Colliery Cumbria

• The Broughton Moor armaments depot opened on the colliery site in 1939 according to the depot article, or 1938 according to the halt article; it closed on 31 December 1992 and the spoil heap remains. (disputed)

Bullhouse Colliery South Yorkshire

• One account of the water drift gives 1915 as the year the mine was abandoned; the caption to the remediation scheme photograph gives 1918 for the closure of the old Bullhouse working. Neither sits easily with the Lists of Mines returns showing the colliery at work in 1947 and 1954. (disputed)

Burghlee Colliery Midlothian

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Burghlee' (catalogue S3952, No.1 Ironstone, Gas & Great, dated 1876); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Buriton Chalk Pit Hampshire

• The British Portland Cement Company bought the site in the 1927 estate sale and the works were all closed in 1939. (disputed)
• The former chalk quarry was worked up to the end of the Second World War. (disputed)
• In spite of blasting at faces some sixty feet high, the most serious accident recalled at the works was a broken leg. (uncertain)

Burrow Farm Mine Somerset

• The engine house is dated to 1879 by the Geograph record and by accounts of the mine's reopening; the Exmoor HER and some published summaries give 1880. Either way it stood for at most four working years before closure in 1883. (disputed)

Bursledon Brickworks Hampshire

• The brickworks were founded in 1897 by Robert and Edward Ashby of the builders’ merchants Hooper & Ashby, the company being renamed the Bursledon Brick Co. Ltd in 1903. (uncertain)
• A local history instead dates the founding to 1896 and credits it to Edward Hooper’s partnership with the Ashby family. (uncertain)

Bwa-Drain Mine Ceredigion

• The BGS / Mining Remediation Authority catalogue lists a plan titled 'Bwadrian's Mine or Dol Fawr', referenced SN77NW 8 — the same map sheet as Coflein's record for Bwa-Drain; it may be this mine. (uncertain)

Bwlchgwyn Mine Ceredigion

• The BGS mine-plans catalogue holds a BGS plan titled 'Bwlchgwyn Mine' (catalogue -, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Cadder Colliery East Dunbartonshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Cadder' (catalogue 7952, Shaft Section, dated 1923); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Cadley Hill Colliery Derbyshire

• The Derbyshire Historic Environment Record states that even after the decline in production in the 1960s, Cadley Hill continued to be a significant employer, with 3,500 men at work and an average production of two million tons of coal in the early 1980s. (uncertain)

Cae Coch Sulphur Mine Conwy

• The Geological Conservation Review records the Cae Coch massive stratabound pyrite deposit as of controversial origin, variously interpreted as an altered ooidal ironstone, an epigenetic fracture-fill and a kuroko-type volcanogenic exhalative deposit, with the most recent examination classing it as a syn-diagenetic inhalative body formed by bacterial sulphate reduction in anoxic muds. (disputed)
• A June 2018 report describes vividly coloured mineral deposits and acidic pools in the upper levels, comparing the interior to 'being inside a volcano', while noting the sulphur smell was much fainter than expected and that the mine has two natural exits allowing air to circulate. (uncertain)

Caerau Colliery Bridgend

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Caerau' (catalogue SWA1012, Caerau, dated 1967); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Caerbryn Colliery Carmarthenshire

• Welsh Coal Mines gives 69 men at the No. 2 Slant, working the Rock, Green and Yard, and 160 at the New (No. 3) Slant in the Pumpquart and Stanllyd in 1923, with the pit having ceased production. (disputed)
• The mine-plans catalogue holds a Caerbryn abandonment plan for a Wenallt seam dated 31 March 1960. (uncertain)

Califat Coal Mine Leicestershire

• There are two engine house complexes at the Califat mine, the easterly one named Alabama, believed to be named after the CSS Alabama which sank or captured sixty-four United States merchantmen during the American Civil War. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Califat' (catalogue EM1233, Main (Upper Main), dated 1869); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Cambria Mercantile Colliery Neath Port Talbot

• Employment grew from 77 men in 1907 to a 1912 peak recorded as either 148 or 122 men; the colliery was renamed or replaced by Ynysgeinon (Ynisgynon) around 1914–15 under new ownership. (disputed)

Cannock Chase No. 8 Colliery Staffordshire

• One source gives 1862 as the opening year of Cannock Chase No. 8, rather than the 1868 date already recorded here; kept as an unreconciled alternative rather than overriding the existing, more specific date. (disputed)

Cannock Old Coppice Colliery Staffordshire

• Ownership is recorded two different ways: B. Johnson (1865-70), J. Owen & Co. (1875) and the Coppice Colliery Co. (from 1880); or the Coppice Colliery Co. itself opening the pit new in 1894. Not reconciled here. (disputed)
• Cannock Chase District Council, the site's current owner, gives 1893 as the opening year and 1964 as the closure year -- a third account differing from both ownership chronologies already recorded. (disputed)

Canonbie Colliery Dumfries and Galloway

• Wikipedia's account of the coalfield states that Canonbie colliery was worked until 1920, while the separate mine at Archerbeck continued until 1942. (disputed)

Caprington Colliery East Ayrshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Caprington' (catalogue S1500, Splint, Turf And Wee, dated 1915); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Carrock Fell Mine Cumbria

• A June 2012 report describes the group cutting their underground visit short after encountering bad air in the deepest workings, having explored adits featuring quartz veins and a horseshoe-shaped formation. (uncertain)

Carronhall Colliery Falkirk

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Carronhall' (catalogue 13904, Lower Coxrod, dated 1945); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Carshield Mine Northumberland

• By 1880 the lead deposit was regarded as exhausted, but in 1899 the Vieille Montagne Zinc Co reopened the workings to mine for zinc ore and mining continued until 1913. (disputed)
• The 1914 List of Mines records Carshield at West Allendale under the Vieille Montagne Zinc Co. of Nenthead, working lead ore and zinc ore, with 88 employed underground and 2 at surface. (disputed)

Catherton Colliery Shropshire

• The official 1880 return names J. Patchett and Co. as the owner of Catherton Colliery, while the scheduling text records Summers and Garbett as operating it until 1889. Nothing located reconciles the two. (disputed)

Cawdor Colliery Carmarthenshire

• 1923: 401 underground and 77 surface; 1930: 499 men, although the Colliery Guardian of April 1930 said it had been closed for three years. (disputed)
• Old maps show Cawdor Colliery at SN 675 114, with an air shaft near Pen-y-waun and a tramway down to Glanamman; the compiler calls it 'Old Cawdor' and thinks Garnant Colliery was at some point called 'New Cawdor'. (uncertain)
• NMRS gives the original slant at 076115 and the 1896 opening, also called North Amman, at 092115; neither is a valid six-figure reference as printed. (uncertain)

Cefn Coed Colliery Neath Port Talbot

• Material from the Dulais Seam here was identified by X-ray diffraction as 'amesite or chrysotile' — an unusual, unresolved occurrence in Coal Measures strata rather than a confirmed chrysotile locality, and one of only two possible chrysotile records anywhere in Wales. (disputed)

Cefn Parc Arlais Colliery Neath Port Talbot

• Renamed Cefn Parc Arlais when David Lewis took sole charge; Welsh Coal Mines dates this to 1954, when it worked till 1958 with output of 6,017 tons in 1957 alone, but NMRS dates the closure-and-reopening-under-the-new-name to 1956. (disputed)

Celynen Colliery Caerphilly

• Within seven weeks in early 1915, three further men died at Celynen South in separate runaway-dram incidents: timberman Frederick Reed (42) on 2 March, and repairer Walter Bennett (40) and roadman John Vaughan (28, died six days later of his injuries) together later that month. (uncertain)

Chaloner Ironstone Mine North Yorkshire

• The Durham Mining Museum dates the mine October 1869 to 12 August 1939; the local history society's timeline has a Chaloner ironstone mine opened just north of Guisborough in 1853. (disputed)

Chanters Colliery Greater Manchester

• Chanters was commenced on a very old site; its 'Gold Pit', an engine pit, is said to have ceased before 1800 and to be named from a find of Charles I gold coins and their stamping plates. (uncertain)

Charlestown Limeworks Fife

• Sources disagree on the end of the works: most of the complex closed in 1935 as the operation ran down from the 1930s, Wikipedia gives final closure in 1956, and Canmore's excavation report refers to the limeworks having been abandoned in 1957. (disputed)

Chatterley Whitfield Colliery Staffordshire

• It has been suggested coal was worked here as early as the 14th century by the Cistercian monks of Hulton Abbey, but the first firmly documented activity dates from 1750. (uncertain)
• A September 2022 report on a permission visit describes the Hesketh Heapstead as being at risk of collapse in the near future, and notes that most buildings remain fenced off and inaccessible despite £20,000 of roof repairs to the pithead baths building. (uncertain)

Chilton Colliery County Durham

• Chilton was originally a mining town called Chilton Buildings. The mine stood on the site of the present primary school, and the miners lived at Windlestone Colliery in terraces named Albert Street, Arthur Street and Prospect Terrace, known locally as the Five Rows. (uncertain)

Chislehurst Caves Kent

• In 1903 the archaeologist William Nichols proposed that the workings were dug by Druids and extended by Romans and Saxons, and the three sections are still named accordingly on tours. (disputed)
• Contemporary scholars disputed Nichols's theory, holding that most of the excavation had taken place within the previous two centuries, and the claim remains unverified; an 1862-63 Ordnance Survey map shows the site as a chalk pit with kilns and an engine house. (disputed)
• A 9th-century Saxon charter is cited as the earliest mention of the site, with no further reference until about 1232; the earliest documentary evidence of the chalk workings themselves dates to 1737, and mining is thought to have ceased in the 1830s or 1840s. (uncertain)

Chislet Colliery Kent

• Coal was reached at 1,350 ft (411 m) in 1919, after the cementation process was used to consolidate the chalk; some accounts date first production to 1918. (uncertain)

Church Burn Mine Northumberland

• The 1884 plan depicts only the first 140 m of the East Vein level, suggesting it was impassable beyond that point by then, and it seems probable the mine lay unworked between 1854 and 1884, though the extent or date of any exploration in those years is unknown. (uncertain)

Clashach Quarry Moray

• Its stone is also reported to have been used in the extension to the National Gallery in Edinburgh, the 9/11 memorial in New York, Barcelona Cathedral and the continuing construction of the Sagrada Familia. (uncertain)

Clearwell Caves Gloucestershire

• In 1838 the Birmingham ironmaster G. E. Jackson sank the Old Sling ore mine into earlier workings at Clearwell Meend; by the mid-1860s it alone employed close to 100 men. Sources differ on when large-scale iron-ore extraction in the area finally ended — as early as around 1930, as cheap Spanish ore imports undercut the Forest's mines, or as late as shortly after the Second World War. (disputed)
• Sources differ on the exact date and cause of the Mine Law Court's collapse: the Royal Forest of Dean Freeminers Association records its papers as stolen from the Speech House in 1777, while the Victoria County History records them as having simply 'disappeared' from the Speech House in 1775 — after which assemblies of Free Miners grew increasingly infrequent through the 1820s, before the Dean Forest (Mines) Act 1838 placed the custom on a statutory footing. (disputed)

Cleworth Hall Colliery Greater Manchester

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Cleworth Hall' (catalogue NW23, Brassey, dated 1951); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Cliff Mine North Yorkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Cliff' (catalogue OM2082, Ironstone Cleveland, dated 1887); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Clifton Hall Colliery Greater Manchester

• On the traditional account the men struck over underground safety in 1869, Andrew Knowles and Sons refused to concede, and after some weeks miners were brought in from the Black Country and given the houses the strikers had lived in — 'Bilston scabs', after whom the district was known for many years as Little Bilston. (disputed)
• Cutler's 2018 reading of the newspapers puts the dispute earlier and differently: discontent in 1866 over the banning of a trade union, and the Wigan Observer reporting locked-out miners evicted that year and replaced by two hundred men brought from Cornwall and three hundred from Staffordshire, with about twice as many again arriving at their own expense. By 1885 every man killed in the explosion had a local address. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Clifton Hall' (catalogue NW1024, Crombouke, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Cligga Head Cornwall

• A 2019 underground exploration report describes a recent collapse in the giant stope at Cligga Head and unstable ground in places, with a short modern ladder used to pass between the stope and the middle level. (uncertain)
• An account published in 2024 of a guided descent made in August 2010 describes ladders and tight passages, a surviving Cousin Jack chute, and mineral staining across the cliff face where the fissures and adits that drained the mine to sea level break out; extensive remains of open works, buildings, shafts and spoil tips survive on the headland. (uncertain)
• After the 1945 closure the mine was reopened between 1962 and 1965, and further attempts at revival came to nothing once the tin price collapsed in 1985. (uncertain)

Clipsham Quarry Rutland

• The London Stone is made of Clipsham stone and dates back at least to about 1100. (uncertain)

Clogau Gold Mine Gwynedd

• Every British royal wedding ring since 1923, when the future Queen Elizabeth The Queen Mother married the Duke of York, has reputedly been made from a nugget of Welsh gold sourced from Clogau — including those of Queen Elizabeth II, Princess Diana, and Meghan Markle in 2018. (uncertain)
• A 2022 report describes extensive surviving surface infrastructure at Clogau, including a horse whim, the ruins of a mine office and workshop, and remnants of a steam-powered mill, alongside stopes and deep shafts on the St David's and No. 2 levels either side of the hill's central fault. (uncertain)
• The BGS mine-plans catalogue holds a BGS plan titled 'Clogau' (catalogue KP19209, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Coalbrook Vale Colliery Blaenau Gwent

• Welsh Coal Mines says Brewer was believed related to the Darbys of Coalbrookdale, hence the name; Wikipedia says he came from Coalbrookdale; Out of the Blue Artifacts calls the name an English derivation of Nant-y-glo, 'stream of coal'. (disputed)
• The Coalbrookvale Colliery closed in November 1924, and in October 1927 its equipment was for sale. (disputed)
• The colliery closed in about 1938. (disputed)

Cocken Colliery County Durham

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Cocken' (catalogue 1446, Low Main, dated 1883); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Cocklakes Mine Cumbria

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Cocklakes' (catalogue OM15240, Gypsum And Anhydrite, dated 1966); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Coed Cae Tillery Colliery Blaenau Gwent

• P.S. Phillips owned and worked the level until its July 1888 abandonment, managed by T.P. Stewart in 1878; one source dates his ownership from 1857, another from 1880. (disputed)

Coedely Colliery Rhondda Cynon Taf

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Coedely' (catalogue SWR3799, No.2 Rhondda, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Coegnant Colliery Bridgend

• The Lists of Mines record 1,592 people employed in 1915 (1,422 below ground, 170 at the surface). (disputed)
• A secondary account states that manpower had risen to 1,900 by the outbreak of the First World War. (disputed)
• The colliery's headframe was encased in concrete, described by one local photographic account as an almost unique feature among Welsh collieries. (uncertain)

Coetmor Quarry Gwynedd

• The Royal Commission's study states that the standard gauge railway reached Bethesda in 1884 and that its terminus, on the north side of the town, was built on land reclaimed from the Coetmor Quarry tip. (disputed)
• The Dyffryn Ogwen community history instead says the 1884 station was built on the rubble tips of the former Bird's Lodging slate quarry. (disputed)

Coly Colliery Merthyr Tydfil

• The Dowlais Iron Company's own account of its 1887 closure ties the Colly levels' end to that date, but the more detailed level-by-level record instead places closure of all the levels at 1925, consistent with a separate account of Dowlais's 1924 colliery holdings that no longer names Coly separately. (disputed)

Combs Colliery West Yorkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Combs' (catalogue 2047, Old Hards, dated 1887); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Coniston Copper Mines Cumbria

• Some accounts suggest mining could date back to the Bronze Age, based on mortar stones resembling those from the prehistoric Great Orme copper mines in Wales, but no datable material evidence for activity this early has been found at Coniston. (uncertain)
• A 2015 underground exploration report describes the deeper workings as an unstable, gradually collapsing environment, with sections of hanging rail line and old wooden "false floors" concealing drops — consistent with the site's general reputation for genuinely hazardous underground conditions away from the surface trails. (uncertain)

Conlig and Whitespots Lead Mines County Down

• Mining ended when a descendant of the First Marquis of Dufferin and Ava bought out the mining leases, reportedly owing to his dislike of heavy industry so close to his residence, rather than exhaustion of the ore. (uncertain)

Cononish Mine Stirling

• A January 2009 report, made before large-scale operations resumed at Cononish, describes mining equipment including tipper trucks and an excavator still standing underground, along with visible gold in the rock and a narrow older adit that leads out behind a waterfall. (uncertain)
• Mining at Cononish effectively stopped at the end of September 2023 when staff were laid off, and the site went onto care and maintenance with a core team retained for environmental monitoring. Reporting in March 2025 said a South African group had bought the mine and intended to recapitalise it and restart production. MineArchive has not confirmed whether production has in fact resumed. (uncertain)
• A monitoring report of June 2023 rated eight of the mine's planning conditions red and five amber. Among them was the settlement pond, still unrepaired after fifteen months of promised work, which Parkswatch Scotland reports had leaked polluted water into the River Cononish from the start. (uncertain)

Consolidated Mines Cornwall

• Wikipedia dates Consolidated Mines' formation to 1782, from the merger of Wheal Virgin, West Wheal Virgin, Wheal Girl, Wheal Maid, Wheal Fortune and Carharrack Mine. (disputed)
• Cornwall Calling instead dates the mine's formation to 1780. (disputed)
• Wikipedia records Consolidated Mines ceasing work in 1857 and amalgamating with United Mines and Wheal Clifford in 1861 to form Clifford Amalgamated Mines, which continued unprofitably until 1870; Grace’s Guide gives the closure as 1858 and the amalgamation with United as 1857. (disputed)

Conygre Colliery Somerset

• The Durham Mining Museum's returns give the colliery as opened in 1791 and closed in 1918, with the Lower pit, sunk 1847, closed in March 1914. (disputed)
• The Timsbury accounts state that both Upper and Lower Conygre closed in 1916, ending coal mining in the village. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Conygre' (catalogue SWR3345, Unnamed Seam "X" "Y", undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Cossall Colliery Nottinghamshire

• The Historic Environment Record gives the colliery as opened in 1870 and closed in 1966. (disputed)
• The parish's own history says the colliery was sunk in 1878-79 by the Cossall Colliery Co., while the Lists of Mines record it worked from 1871 and the register of deaths at the pit and its earlier workings begins in 1868. (disputed)

Cotgrave Colliery Nottinghamshire

• On closure it was reported that the seams held millions of tons of reserves but of insufficient quality. Local residents instead recount geological faults, the encounter of a subterranean stream and subsequent flooding, and the growing distance of the seam face from the shaft, which drastically increased the cost of bringing coal to the surface. (disputed)

Cove Quarries, Coniston Cumbria

• The Coniston Local History Society reported in 2010 having received a family account of operations at Cove from about 1855 to the middle of the twentieth century. (uncertain)

Cowden Furnace Kent

• An iron furnace at Cowden is recorded in 1574 and 1588, possibly established by John Tichborne (a mill on the site was 'proved' in 1556); it was ruined by 1664. Early ironmasters named in connection with Cowden's furnaces include Quyntyn and Michael Weston, though without precise dates in the surviving record. (uncertain)

Cragg's Hall Mine North Yorkshire

• A family history of east Cleveland ironstone miners attributes a Cragg Hall ironstone mine at Carlin How to Bell Brothers, working from 1871 to 1892. Bulmer's directory of 1890, written while the mine was at work, gives it to Pease and Partners. The directory is the better authority and this record follows it; the discrepancy is recorded rather than resolved. (disputed)

Craigend Colliery, Maddiston Falkirk

• The Lists of Mines give 812 employed in 1920 and 1923; the Falkirk Local History Society says over a thousand men and 1,100 tons a day by the 1920s. (disputed)

Crenver & Wheal Abraham Cornwall

• The mine traded as the Crenver and Wheal Abraham United Mining Co. Ltd. (also recorded as Crenver and Wheal Abraham United Mines Co. Ltd.), appearing in Parliamentary returns of registered Cornish and Devon joint-stock mining companies during the 1860s. (uncertain)

Cribbwr Fawr Colliery Bridgend

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Cribbwr Fawr' (catalogue SWR1304, Five Feet (Nive Feet), dated 1930); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Crich Limestone Quarries Derbyshire

• Stephenson constructed a metre gauge line — apparently the first metre gauge railway in the world — and superintended the construction himself; it included two tunnels and two self-acting inclines. (uncertain)

Crigglestone Colliery West Yorkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Crigglestone' (catalogue NE656, Low Haigh Moor, dated 1969); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Croft Granite Quarry Leicestershire

• Local tradition holds the site was worked as a Roman quarry in the 1st century AD for road and bridge foundations, though this claim is not corroborated by scholarly sources. (uncertain)

Crofthead Colliery West Lothian

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Crofthead' (catalogue 7923, Mill, dated 1916); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Crossfield Mine Cumbria

• The BGS mine-plans catalogue holds a BGS plan titled 'Crossfield;' (catalogue SP2340, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Crynant Colliery Neath Port Talbot

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Crynant' (catalogue SWR3772, No2 Rhondda (Ynisarwed), undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Cwm Cynon Colliery Rhondda Cynon Taf

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Cynon Level' (catalogue SW146, Wernddu (No 2 Rhondda)., dated 1952); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Cwm Rheidol Mine Ceredigion

• The BGS mine-plans catalogue holds a BGS plan titled 'Rheidol Mine' (catalogue -, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Cwmaman Colliery Rhondda Cynon Taf

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Cwmaman' (catalogue SWR1207, Six Feet, dated 1914); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Cwmbran Colliery Torfaen

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Cwmbran' (catalogue 1983, Meadow., dated 1886); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Cwmceiros Colliery Neath Port Talbot

• NMRS's own compiler could only assume Cwmceiros was the same level as the neighbouring Cwmnantllwyd Colliery, but an independent local-history account of the district's old mines lists Cwm Ceirios Drifts (working the Pretoria and South Wales Four-Feet seams) as a separate entry from Cwmnantllwyd Pit and Drifts (working the South Wales Four-Feet, Graigola and Upper Maesmelyn seams) — suggesting they may genuinely be two adjoining, not identical, workings. (uncertain)

Cwmclydach Graigola Colliery Neath Port Talbot

• An independent local-history account of the same site states operations continued until 1925, the last of the old Clydach collieries to use the Swansea Valley Canal — an earlier closure than NMRS's own record of activity into 1930-32; the discrepancy is not resolved here. (disputed)

Cwmgwili Colliery Carmarthenshire

• In 1972 the NCB merged Cwmgwili with the old Lindsay Colliery at a cost of £150,000. (disputed)
• In 1970 a £170,000 scheme merged the two mines. (disputed)
• Officially closed in the early 1980s but 21 men worked pillar and stall until 1992; after UK Consolidated Mining, Coal Investments and a failed Jewel Limited buy-out it really closed on 21 November 1996. (disputed)
• It was closed by British Coal in 1980 but kept working under Coal Investments plc; production ceased in 1994. (disputed)

Cwmgwrach Colliery Neath Port Talbot

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Cwmgwrach' (catalogue SW222, Nine Feet, dated 1954); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Cwmllynfell Colliery Neath Port Talbot

• In 1825, 59 men were killed in an explosion. (uncertain)

Cwmorthin Slate Mine Gwynedd

• A July 2014 report describes severely deteriorated conditions in the Old Vein workings, with numerous roof falls and delaminating slabs, alongside abandoned mining carts still standing on Floor B and miners' barracks visible from the surface. (uncertain)

Cwmtillery Colliery Blaenau Gwent

• Thomas Brown acquired the right to sink at Tir Nicholas farm in the 1840s in the hope of reaching the Elled seam; the shaft was sunk to 130 yards. (uncertain)
• John Russell took ownership in 1852, increased the original shafts and deepened the mine to 240 yards. (uncertain)
• Four underground explosions are recorded at the colliery between 1857 and 1876. (uncertain)
• An explosion on 27 May 1857 killed thirteen, among them the fireman Samuel Merrifield, 29, and the collier Charles Merrifield, 58. (uncertain)
• The colliery closed in 1982. (uncertain)

Cwmystwyth Mines Ceredigion

• Average miner lifespan at Cwmystwyth has been estimated at just 32 years, attributed to acute lead poisoning from the ore being worked. (uncertain)
• A September 2018 report on Level Fawr describes an original mine dram still in place underground, alongside evidence of relatively recent maintenance such as newly installed ladders. (uncertain)

Cwrt Herbert Colliery Neath Port Talbot

• Welsh Coal Mines gives 269 employed in 1923; the Durham Mining Museum returns 332. (disputed)

Cymmer Colliery Rhondda Cynon Taf

• The Cymmer Old Pit was worked by the Insole company until the mine closed in 1939. (uncertain)

Dalmellington Iron Works East Ayrshire

• A 2011 report describes the surviving 1847 engine house and brickworks kilns as 'complete but out of use', with an undercroft beneath the engine house — investigated by removing part of its cement floor — found to extend at least 2.3 metres down and to contain cast-iron girders and cover plates from the original beam-engine blast system. (uncertain)

Darnley Lime Works Glasgow

• Sources differ on where the works sit. The Scottish Cave and Mine Database gives Darnley Park, Nitshill, City of Glasgow (Renfrewshire); Wikipedia places the tramway and works in East Renfrewshire, 9.7 km south-west of Glasgow. The country park straddles the boundary. (disputed)

Darran Colliery Caerphilly

• The colliery was sunk in 1868 by the Rhymney Iron Company, with two shafts each reaching the Brithdir house-coal seam at 120 yards. (uncertain)
• Until the explosion of 29 October 1909 the mine was considered safe, and throughout its history it had been worked with naked lights. (uncertain)
• The colliery employed 272 men in 1908 and only seventy-three by 1918. (uncertain)
• The Darran was connected underground to Gilfach colliery; survivors of the 1909 explosion made their way out through the Gilfach shaft, and the rescue party went in that way. (uncertain)
• The colliery closed in 1919. (uncertain)

Deaf Hill Colliery County Durham

• Deaf Hill lies a short distance east of Trimdon Colliery and is alternatively known as Trimdon Station. Local tradition holds that the place was originally Death Hill, from a belief that children passed through the fork of a sycamore there would be cured of diphtheria; they died, and the name was changed as more people settled. (uncertain)

Deeside and Moelfferna Quarries Denbighshire

• Wikipedia gives 1947 for the closure of the enterprise; the Royal Commission's record says the Moel Fferna mine closed in 1960. (disputed)

Denaby Main Colliery South Yorkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Denaby Main' (catalogue M781, Barnsley, dated 1871); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Denend Colliery Fife

• The colliery was probably sunk in the 1860s and is believed to have ceased coaling in 1895. (uncertain)

Desford Colliery Leicestershire

• In the 1950s Matthew Smith, the undermanager at Desford Colliery, invented the Desford Chock, described as the first ever hydraulic powered roof support; Sam McKee, the mine agent, developed it further, and three prototypes were tried using the colliery fire hydrant to supply the water pressure. (uncertain)

Devon United Mine Devon

• Three figures are on record for the tin. The Historic Environment Record gives 367 tons of black tin for 1904-9 and 1912-22; the Geological Conservation Review gives 373 tons of tin concentrates for the group; Devon in Focus gives 387 tons of black tin for 1852 and 1905-13. (disputed)

Digby Colliery Nottinghamshire

• One published brickworks history gives the colliery's closure as 1928, which is contradicted by the 1933 Year Book listing and a fatality at the pit in March 1934. (disputed)
• The colliery closed in 1937, the year the company's New London Colliery shut; a widely repeated date of 5 November 1937 has not been traced to a readable source. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Digby' (catalogue 10011, Tupton, dated 1930); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Diglake Colliery Staffordshire

• Wikipedia gives three shafts of 790, 745 and 460 feet, the third formerly part of the adjacent Boyles Hall Colliery. (uncertain)

Dinorwig Slate Quarry Gwynedd

• A 2023 report describes the quarry's upper levels, including the Australia Mill and its compressor house, as remaining in 'remarkable condition, with many of the buildings and artifacts remaining in place', preserved by minimal disturbance since closure. (uncertain)

Diphwys Casson Quarry Gwynedd

• Coflein and a 2020 site survey both record small-scale extraction continuing to 1925; Wikipedia instead describes a 1920s reopening lasting seven years before a final 1955 closure. (disputed)

Dockra Ironstone Pit North Ayrshire

• Sunk in 1896 and closed in 1918 according to the museum; the village history says it worked until the 1921 strike. (disputed)

Dolaucothi Gold Mines Carmarthenshire

• A small quantity of gold from Dolaucothi was reportedly used in commemorative items for Prince George's 1934 wedding. (uncertain)
• Archaeological evidence suggests gold extraction at Dolaucothi may have begun as Bronze Age washing of gold-bearing gravels along the River Cothi, predating the Roman hushing and underground operation. (uncertain)

Dolcoath Mine Cornwall

• Grace's Guide records Dolcoath as producing over 350,000 tons of copper across its working life and over 100,000 tons of tin between 1853 and 1920, and values total mineral production at over £10 million — against the figure of over £9 million for 1799-1920 given elsewhere. The two are not directly comparable, covering different periods. (disputed)
• Sources disagree on the closing year: most give 1920, while Grace's Guide records operations ceasing in 1921. (disputed)

Donibristle Colliery Fife

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Donibristle' (catalogue 7896, Lower Splint Or Dunfermline Splint, dated 1928); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Donisthorpe Colliery Leicestershire

• I.A. Recordings, whose crew were on site that day, record the colliery as officially due to close at twelve noon on 12 April 1990; the Wikipedia article on the village gives the closure as 1991. (disputed)

Dorothea Quarry Gwynedd

• The 68-inch Cornish beam engine was designed by Nicholas Trestrail and built by Holman Brothers of Hayle; work began in April 1905 and the engine was set going in June 1906. (disputed)
• The Cornish beam engine is recorded as installed in 1904. (disputed)

Doura Colliery North Ayrshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Doura' (catalogue 5895, Firec;Ay, dated 1912); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Doward Iron Mines Herefordshire

• Camden recorded a giant skeleton found in a cave on Great Doward Hill, later called King Arthur's Hall, which Nicholls took to be the entrance to an ancient iron mine. (uncertain)
• The ancient Dean iron workings, including those on the Doward, have the appearance of spacious caves or of irregular passages left by the removal of ore, followed for hundreds of yards with openings made to surface. (uncertain)
• Forest of Dean Deputy Gaveller's records showed only two small mines here with dates in the last quarter of the 19th century, plus two undated shafts on the edge of the complex. (uncertain)
• The only working remembered locally was in 1917, when one of the mines was reopened and several truckloads of ore sent off by rail. (uncertain)

Dowgang Mine Cumbria

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Dowgang' (catalogue OMR46C, Lead Ore, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Dubs Quarry Cumbria

• The published history of Honister gives 1932 as the year Dubbs Quarry ceased production, largely because of the difficulties and slowness of transporting finished slate. (disputed)
• The Durham Mining Museum's transcription of the 1929 List of Mines records against Dubs that it had not been worked since 1927. (disputed)

Duffryn Rhondda Colliery Neath Port Talbot

• Sunk 'sometime prior to 1880' by the Duffryn Rhondda Coal Company as a slant and two shafts (Coflein; Welsh Coal Mines). (disputed)
• Manpower is recorded from 1899 (143 men); a miners' railway platform opened as Duffryn Rhondda Colliery in 1898; sinking of the two deep shafts began in June 1903 under the company registered on 12 January 1903. (disputed)
• The workforce reached 1,500 by 1910 (Welsh Coal Mines; Coflein). (disputed)
• NMRS manpower: 682 in 1905, 954 in 1910, 1,042 in 1912, 692 at the pits and 426 at the levels in 1913-15. (disputed)
• Listed as 'Duffryn Navigation Colliery, Cymmer' in the NMRS Afan Valley small-collieries roundup: owned 1920-24 by the Imperial Navigation Coal Company, managed by D. J. Rees, 1,200 men in 1920-24, 1,300 in 1925-26 and 850 in 1929. (disputed)
• The NMRS colliery page lists 200 men in 1920, 300 in 1922 and 1924-25, but 1,590 in 1923 (No.1 pit 750, No.2 pit 550, No.2 slant 290) with an output of 360,000 tons; the 200 and 300 figures look like misprints for 1,200 and 1,300. (disputed)
• Coflein and Welsh Coal Mines give the closure as 1966/7. (uncertain)

Dunkerton Colliery Somerset

• The closing year is given as 1925 by one source and 1933 by another; the Lists of Mines still return three people at the colliery in 1933. (disputed)

Dunnikier Colliery Fife

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Dunnikier' (catalogue S4377, Cardenden Smithy, dated 1902); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Dunraven Colliery Rhondda Cynon Taf

• Dunraven Colliery's early ownership is not cleanly documented: David Davis and Sons (c.1860-65), Thomas Joseph (mid-1860s-1880s, with a 1866 liquidation), and the Dunraven United Collieries Co. Ltd (1869-70) all appear in records without a clear reconciliation of how these periods relate. (disputed)
• An alternative, detailed account of the colliery's 1858-1893 ownership has Thomas Joseph as sole owner from 1858 until an 1882 bankruptcy (liabilities of £130,000), then the South Yorkshire Building Society (1882-91), then F. R. Crawshay of Swansea (1891, for £26,000, bankrupt by September 1893) -- distinct from, and not reconciled with, this record's other account naming David Davis and Sons, Watts and Company and the Earl of Dunraven across the same broad period. (disputed)

Durie Colliery Fife

• Opened in 1855; the museum closes it at 1900 but lists deaths there in 1902 and 1903. (uncertain)

Dylife Powys

• The 1858 transfer of the Dylife mining interests to the Dylife Mining Co. Ltd involved the prominent Victorian politicians Richard Cobden and John Bright. (uncertain)
• A site visit in September 2010 found the Martha Wheel pit — the wheelpit of the Rhod Goch — some 40 ft deep and restored in 2005, with the Llechwedd shaft, several adits and old lead flues traceable among the spoil, and wooden pipework surviving near one adit mouth. The visitor described the stream disappearing and reappearing repeatedly into old workings, frequent collapses, and new adits opening after heavy rain. (uncertain)
• Accounts differ on how big the settlement grew: the figure usually given is over a thousand people, while Powys County Archives puts the community at around 1,500 at its height. (uncertain)

Earnock Colliery South Lanarkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Earnock' (catalogue 13228, Ell, dated 1942); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Easdale Slate Quarries Argyll and Bute

• The record's own account and the scheduling text give 250 feet below tide level for the quarry flooded in 1881; easdale.org says some of the island's seven quarries extended to 300 feet below sea level. (disputed)

East Ardsley Colliery West Yorkshire

• The memorial on Moor Knoll Lane remembers the men who worked and died at East Ardsley Colliery, 1872 to 1966. (disputed)

East Benhar Colliery West Lothian

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Benhar' (catalogue S412, Ball, dated 1962); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

East Gawber Colliery South Yorkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Gawber' (catalogue 8094, Barnsley, dated 1925); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

East Pool Mine Cornwall

• Sources disagree on the date the Taylor's Shaft pumping engine was built: the National Trust's own record gives 1891, built by Harvey & Co of Hayle for £5,500 and first installed at Highburrow East Shaft, Carn Brea, while Wikipedia gives 1892. Both agree it was re-erected at Taylor's Shaft in 1924. (disputed)
• Sources also disagree on when the Taylor's Shaft engine stopped: the National Trust records it working from 1925 until 1955, while Wikipedia gives 28 September 1954 as the date electric pumps took over. (disputed)

Easthouses Pit Midlothian

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Easthouses' (catalogue S675, Great Seam, dated 1971); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Eccleston Quarry Lancashire

• A local resident said that during the Second World War a Ministry paid a local man to run a pump at intervals to keep the quarry empty while its owner and staff were away, and that after the war an official reorganisation stopped the payments, so the man stopped running the pump and the quarry flooded. (uncertain)

Eckington Mine Derbyshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Eckington' (catalogue 18210, Deep Soft, dated 2012); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Ecton Copper Mines Staffordshire

• The Ecton Mine Educational Trust's own history gives the mine's final abandonment as 1889. (disputed)
• Wikipedia gives the mine's final closure as 1891. (disputed)
• The 1788 Boulton & Watt engine house on Ecton Hill is reputed to be the oldest surviving engine house built for winding ore out of a mine anywhere in the world. (uncertain)
• Profits from the Duke of Devonshire's mining at Ecton in the 18th century are said to have helped finance the building of the Crescent at Buxton. (uncertain)
• A June 2024 report describes the Whey Adit (originally Birches Level, later used by a nearby creamery to store whey) as a straight 213-metre passage, rough underfoot with remains of old drainage infrastructure, ending at a flooded section. (uncertain)

Edmondsley Colliery County Durham

• Durham Mining Museum dates the colliery’s opening to the 1850s; the parish council’s history puts the village’s beginnings, and the colliery’s opening, at 1840. (disputed)
• The colliery was abandoned on 30 November 1920 and the plans sent to the Mines Department; the parish council’s history gives the closure as 1921. (disputed)

Elba Colliery Swansea

• Welsh Coal Mines says a defective lamp was held responsible for the explosion. The Durham Mining Museum gives the cause as an explosion of firedamp with the ignition caused by contraband — that is, by something a man took below that he should not have. (disputed)

Eldin Colliery Midlothian

• By 1896 the Polton mine at the same place was owned by the Lothian Coal Company Ltd, which existed at least until 1945. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Eldin' (catalogue S2539, Splint, dated 1806); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Elphingstone Colliery East Lothian

• Mining Remediation Authority abandonment plans titled 'Elphingstone' are dated 1882 (Five Foot), 1907 (Great) and 1929 (Splint, catalogue 11609); the 1929 plan may bear on the unestablished closure date. (uncertain)

Elsecar Colliery South Yorkshire

• Henry Ford twice tried to buy the engine to take it to America and was refused by Earl Fitzwilliam. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Elsecar' (catalogue NEST36, Spoil Tip, dated 1987); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Elterwater Quarry Cumbria

• Part of the quarry's underground workings has been proposed for redevelopment as a heritage tourist attraction, a plan that has met public objection locally. (uncertain)

Elwyn Colliery Neath Port Talbot

• NMRS separately records an 'Elwyn Pinetrees' as worked by the Tower Anthracite Company and then, from 1993, by Ward Brothers -- likely the same Elwyn/Graig y Fforest connection described by Welsh Coal Mines, though NMRS's own date range for it ('1911 and 1992') is not consistent with either source's other dates and is probably a transcription error. (uncertain)

Eppleton Colliery Tyne and Wear

• An explosion in the Downs pit on 28 January 1836 killed twenty, with another so badly scorched that there were faint hopes of his recovery. Over a hundred were employed in the pit at the time. (uncertain)

Exhall Colliery Warwickshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Exhall' (catalogue 12452, Seven Feet, dated 1938); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Fallowfield Mine Northumberland

• The mine was probably worked in Roman times — it lies very near the line of Hadrian's Wall — and is thought to have been worked in the Middle Ages by the monks of Hexham Abbey, who used the lead to roof the abbey. (uncertain)

Far Green Colliery Staffordshire

• The colliery was known to its workforce as the Big Pit, Far Green; NMRS's account calls it 'also known as the Deep Pit', but Mould's gazetteer records Hanley Deep as a separate, deeper shaft sunk in 1854, so the identification is disputed. (disputed)

Fauldhead Colliery Dumfries and Galloway

• The Durham Mining Museum names the owners as the Sanquhar and Kirkconnel Collieries Ltd and then Bairds and Dalmellington Ltd before nationalisation; the brick history gives the later private owner as Bairds and Scottish Steel Ltd from 1935. (disputed)

Felinfran Colliery Swansea

• Welsh Coal Mines says the Felinfran Colliery Company opened the colliery, known locally as Garth, in 1931. (disputed)

Felixstowe and Trimley Coprolite Diggings Suffolk

• White's Directory reported in 1885 that the agricultural depression had slackened the manufacture of artificial manures and the raw material no longer had a ready sale; some Suffolk pits stayed in operation until the early 1890s, but no record has been found of when the Trimley workings stopped. (uncertain)

Felling Colliery Tyne and Wear

• The Bensham or Maudlin was worked in two sections at 76 and 88 fathoms, the Low Main at 94 fathoms and the Hutton at 101 fathoms. A Victorian account also gives the 1779 sinking to the High Main as 127 fathoms, which cannot be right for the shallowest seam; it matches the 756 ft upcast shaft instead, and is most likely the shaft depth mis-attributed. (uncertain)

Fenton Park Colliery Staffordshire

• The Victoria Colliery, worked jointly with Fenton Park, had ceased work by 1877 and the Fenton Park Colliery itself closed about two years later. (disputed)
• The official list of collieries at work in 1880 returns a Fenton Park Colliery Co. Limited at Longton, and the North Staffordshire Mining Group’s notes give the same company name for that year. (disputed)

Fergushill Colliery North Ayrshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Fergushill' (catalogue 7378, Wee, dated 1921); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Ferrymoor Colliery South Yorkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Ferrymoor Colliery' (catalogue SFE318, Surface Electrical Plan, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Ffaldau Colliery Bridgend

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Ffaldau' (catalogue SWT1413, Spoil Tip [No.320], dated 1975); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Ffaldydre Colliery Neath Port Talbot

• In 1918 it employed 186 men including 72 on the surface, and 427 in 1924; in 1938, 52 worked underground at Ffaldydre alongside Glyncastle, and 184 in 1945. (disputed)
• NMRS gives 17 men in 1918, 284 in 1919, 403 in 1923 (112,000 tons), 518 in 1930, 135 in 1947, 222 in 1954 and 211 in 1961. (disputed)
• It closed on 28 September 1963 with 211 men, 90 on the coalfaces, because Glyncastle could not retain its manpower and the Ffaldydre men were designated to Glyncastle. (disputed)
• A photograph caption of the return drift gives the mine's abandonment as 28 April 1965. (disputed)

Fforchaman Colliery Rhondda Cynon Taf

• Rhondda Cynon Taf Council gives the sinking as Thomas Brown and Thomas Protheroe in 1856, the pit taking its local name from Brown. H.M. Inspectorate accident records give David Williams sinking it in 1851 and selling to Sir Thomas Phillips in 1858. Both Phillips and Protheroe were Newport coal owners associated with Thomas Powell. (disputed)
• The Northern Mine Research Society gives the sale to Powell Duffryn as 1867 and Welsh Coal Mines as by 1868, while Powell Duffryn's own 1914 booklet says the colliery was purchased in 1866. (disputed)

Fishburn Colliery County Durham

• The Fishburn Coking Plant was built in 1954 alongside the colliery to produce high-grade coke for industry and a domestic coke called Sunbrite, together with by-products including town gas, which was supplied directly to the nearby Winterton Hospital and to the national grid. (uncertain)

Flimby Colliery Cumbria

• The Rattler seam was abandoned as unworkable on account of faults. The colliery record dates this 17 February 1898; the catalogue of abandonment plans dates the abandonment of Robin Hood No. 2 in the Rattler to December 1897. (uncertain)

Flockton Collieries West Yorkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Flockton' (catalogue GCR222, Flockton Thin, dated 1849); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Florence Colliery Staffordshire

• Accounts differ. Staffordshire Past Track dates the colliery 1874 to 1990; Jim Worgan describes the Florence section being closed, its shafts filled and its surface structures demolished after Coal Investments took over the Trentham complex, which followed the closure of the combined mine in 1993. (disputed)

Fochriw Colliery Caerphilly

• An explosion on 10 May 1865 burned fourteen men, a number of whom later died of their injuries; the exact death toll is not established in the sources checked. (uncertain)

Force Crag Mine Cumbria

• Documentary sources record small-scale surface extraction of lead at Force Crag as early as 1578, well before the main 19th- and 20th-century underground workings. (uncertain)
• A March 2020 permission-visit report, made with a National Trust ranger, describes ongoing vandalism at the locked mine buildings, including a break-in using a battery-powered grinder, despite no materials of value remaining on site. (uncertain)

Fordel Mains Colliery Midlothian

• The Scottish Cave and Mine Database places the colliery at NT 363 669 beside Fordel Mains outside Dalkeith, with the site of No. 1 shaft between the Fordel filling station and the Cowden Bog woods. The Durham Mining Museum gives the location as Dalkeith but prints a grid reference, NT159894, which falls in Fife near Crossgates, some twenty miles away and close to the separate Fordell estate. The Dalkeith location is the one the company name and every other detail support. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Fordel Mains' (catalogue 13765, Alecks, dated 1944); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Forge Colliery, Nantyglo Blaenau Gwent

• The victim of the 20 February 1871 gas explosion is named Thomas Williams in one source and David Williams in another; both agree on his age (21), his trade (collier) and that he was fetching candles from a stall known to hold gas. (disputed)

Foulshiels Colliery West Lothian

• Pithead baths were completed in 1935 for 450 men with 37 shower cubicles; Wikipedia gives 600 men. (disputed)

Foxdale Mines Isle of Man

• At points during the mid-19th century Foxdale produced more zinc blende than all other mines in Britain combined. (uncertain)

Foxes Bridge Colliery Gloucestershire

• Accounts differ on when the northern colliery was begun. The Forest of Dean Local History Society dates the new sinking to 1855, after an original colliery of about 1837 near the Speech House was never completed; the Lightmoor Press history has work starting on the southern site in 1855, the shafts flooding before coal could be won, and the move north made by 1869. (disputed)

Foxyards Colliery West Midlands

• The official 1880 List of Mines entry for this pit reads "Foxyards, Tipton, W. Punter", while the same return is the basis for Grace’s Guide listing Foxyards twice among the Earl of Dudley’s collieries. The two have not been reconciled. (disputed)

Frazer's Hush Mine County Durham

• The mine takes its name from a hush — a hydraulic prospecting technique using a breached dam to strip soil and expose bedrock — on the Greencleugh Vein, a western extension of the Red Vein, thought to date from as far back as the medieval period. (uncertain)

Frizington Iron Mines Cumbria

• A working known as Frizington Mine (or Frizington No.1/Frizington Parks Mine, Pit No.1) was worked for iron ore from 1865 to 1880 under Musgrave & Co (1865-70), Gibson, Cook & Musgrave (from 1875) and the Frizington Coal Co (from 1880); it is uncertain whether this was ever a single formally distinct mine or a name loosely applied to whichever workings the Frizington Mining/Coal Companies held. (uncertain)

Frongoch Mine Ceredigion

• The Northern Mine Research Society gives the Belgian-run operation's closure as December 1902, consistent with the hydroelectric plant's recorded 1899–1903 operating span. (disputed)
• Other accounts describe underground mining at Frongoch continuing until around 1910, with the extensive waste tips reworked for zinc during the 1920s before the site was finally abandoned. (disputed)
• A 2012 underground report describes extensively flooded and partly collapsed workings at Frongoch, including a collapsed false floor between two shafts, natural stoping voids, and old wooden roof supports still in place near Williams Shaft. (uncertain)
• A 2011 surface report describes the 1899 Belgian dressing mill at Frongoch surviving only as ruins, with the associated hydroelectric power station down the valley also abandoned but still structurally standing. (uncertain)
• A photograph taken on 27 July 2022 shows the Frongoch site in use as a Range Rover breaker's yard, with vehicles ranked across the former mine ground; the photographer notes how incongruous it looks in country this remote. (uncertain)

Garnant Colliery Carmarthenshire

• The Welsh Coal Mines colliery page states that ten men were killed and names exactly ten, and the Cwmamman History site dedicated to the disaster is titled in memory of the ten. The Welsh Coal Mines list of Welsh mining disasters gives 18 for the same date. (disputed)
• The colliery was known as Pwll Perkins after Perkins and Sons, at one time its owners, and was later purchased by David Pugh, MP, chief shareholder of the Garnant Colliery Company. (uncertain)
• A waterwheel produced the power for the colliery. (uncertain)
• By 1908 the owner was Cawdor and Garnant Collieries Ltd of Garnant, with 69 men working underground and 33 on the surface. The Gors y Garnant pit closed in 1912. (uncertain)

Garngoch Colliery Swansea

• Welsh Coal Mines says No. 2 was not working in 1923; the Durham Mining Museum returns 376 employed there that year. (disputed)

Gasswater Mine East Ayrshire

• The presence of barytes along the Gass Water was known from at least the 1870s, but it was not developed until 1917 by the Hedworth Barium Co. Ltd, who carried out opencast operations and stoping from a single adit until 1921. Other sources give the opening as 1919. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Gasswater' (catalogue 18344, 0800 To 4000, dated 2002); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Gatewen Colliery Wrexham

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Gatewen' (catalogue 8458, Smith, Powell, dated 1924); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Gauchalland Colliery East Ayrshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Gauchalland' (catalogue 8557, Main, dated 1922); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Gedling Colliery Nottinghamshire

• Sources give slightly different depths for the main seams: Gedling Borough Council's own history states 428 m (1,404 ft) to the Top Hard seam, while a separate account gives the High Hazels seam at 368 yards (337 m) and the Top Hard seam at 458 yards (419 m). (disputed)

Geevor Tin Mine Cornwall

• A 2024 report on the preserved site describes lockers in the mine's ‘dry’ (changing room) still marked with the mine's closure date, some still holding personal items and work clothing. (uncertain)

Gellyceidrim Colliery Carmarthenshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Gellyceidrim' (catalogue 9399, Big, dated 1927); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Gethin Colliery Merthyr Tydfil

• A second explosion on 20 December 1865, in the Upper pit, killed 34 men and boys. (disputed)
• The 1865 death toll is given as 36 elsewhere. (disputed)

Gillfoot Park Mine Cumbria

• Working is recorded as having ended in 1915, but the ownership record for the Wyndham Mining Company Ltd runs from 1901 to 1918. The two are not reconciled by any source located. (disputed)

Gin Pit Colliery Greater Manchester

• Sources disagree on the closure date, giving either 1955 or 1958; the buildings were subsequently used by William Hare as a foundry and steel-fabrication plant. (disputed)

Gin Pit, Maesteg Bridgend

• Gin Pit probably originated as Nant-y-Crynwydd Colliery and was opened by the Llynvi Iron Company on the site of its ironworks, probably in the early 1840s; the name is thought to be a shortened form of 'Engine Pit'. (uncertain)

Glanamman Colliery Carmarthenshire

• It was shut on 31 January 1948 with 300 men, one of the old Swansea Area slants the NCB chose to close. (disputed)
• NMRS statistics give 116 men in 1947 and 119 in 1948. (disputed)

Glapwell Colliery Derbyshire

• The No. 2 shaft was the upcast, 306 yards deep and 14 feet in diameter as sunk, deepened in 1924 to 669 yards and 18 feet; a third shaft was sunk between 1920 and 1934 to about 657 yards. These figures sit slightly awkwardly with the same source's statement that 680 yards had been proved by 1918. (uncertain)

Glasshoughton Colliery West Yorkshire

• The Twentieth Century Society's own record of the pithead baths scheme independently confirms the colliery's ownership (Glass Houghton and Castleford Collieries, Ltd.) and its capacity (3,006 men), but gives the opening date as 6 June 1931 rather than the 30 March 1931 already on this record; both dates are kept as the sources disagree and neither has been reconciled. (disputed)

Glebe Mine Derbyshire

• Lead working is recorded as ceasing in 1884 by Mindat and in 1888, when the Eyam Mining Company ceased operations, by the Derbyshire Historic Environment Record. (disputed)

Glenariff Iron Ore Mines County Antrim

• Sources disagree on the exact closure date: Wikipedia gives 1875, when insufficient ore output, labour shortages and depressed prices halted production; the Glens of Antrim Historical Society gives 1881. Both agree the company was sold in a bankruptcy sale in 1885 after defaulting on its ground rent to the Earl of Antrim. (disputed)

Glenbuck Colliery East Ayrshire

• Grasshill, the last working colliery, employed around 150 of the village's roughly 200-strong workforce; Wikipedia gives its closure as 1931, while The Lost Villages and the Mining Remediation Authority's own abandonment record both give 1933. (disputed)

Glendinning (Louisa) Mine Dumfries and Galloway

• The mine's second working phase is dated 1888 to around 1891 in some accounts but 1888-1901 in the Scottish Cave and Mine Database; the exact end date of this phase is not firmly settled. (uncertain)

Gloria Colliery, Hartley Northumberland

• The museum records 304 employed in 1950, the last return before closure. (disputed)
• The site plaque says two hundred men were working there at closure, working out a small reserve. (disputed)

Glyn Neath Colliery Neath Port Talbot

• A 24-year-old screens worker died in a machinery accident on 31 August 1927; NMRS names him M.S. George at Glyn Neath Colliery, while Welsh Coal Mines' fatalities register instead names George Wilfred Williams at the nearby Cwmrhydygau Colliery, both matching on date, age and trade. (disputed)

Glyn Pits, Pontypool Torfaen

• The pits were sunk to a depth of 190 yards. (disputed)
• The two shafts were sunk side by side to 190 feet (58 m). (disputed)
• Production stopped in 1932. (disputed)
• Glyn Pits Nos. 1 and 2 ceased coal winding in 1928 and became a pumping site for Hafodyrynys, finally closing in 1949 under NCB ownership. (disputed)
• The pit was still used as a pumping station for Hafodyrynys until the 1960s; a 2012 account says electric pumps were in use until the site was abandoned in 1966. (uncertain)

Glyncastle Colliery Neath Port Talbot

• In 1935, 750 men worked in 'the Pit'; with Ty'n-y-Cwm and the Tyra levels the collieries employed over 700 men in 1896. (uncertain)

Glyncorrwg Colliery Neath Port Talbot

• Welsh Coal Mines gives the South pit as 403 yards; the Inspector of Mines' 1955 report gives the South Shaft as sunk to the Six Feet Seam at a depth of 407 yards. The report also confirms the South Shaft as the downcast, 18 feet in diameter and the main winding shaft, and the North as the upcast at 16 feet. (disputed)
• The Welsh Coal Mines account reports at second hand, and phrases as a question, that Tower Colliery was later working Glyncorrwg's reserves beneath the village. This is not corroborated by any other source consulted. (uncertain)

Glynmoch Colliery Carmarthenshire

• The Dragon Coal Corporation took over in 1997 and the mine closed for good on 31 May 2000. (disputed)
• E. S. Morris of Gloucester was the licensee in 2000, and the mine was not listed in 2003. (disputed)
• Between 1950 and 1990 it employed between ten and twenty-five men, thirty-seven in 1987; reserves were given as 276,000 tonnes in 1964. (uncertain)
• Entrances recorded at SN 660129 (No. 1 or Ystrad; fan drift and fan shaft) and 655123 (No. 2 or Bodyst), with old shafts at 656125, 655123 and 654122; Bodyst first hauled coal in 1971. (uncertain)
• In 1979 the owner of Ystrad was prosecuted by the Inspector of Mines and Quarries and fined 2,800 pounds. (uncertain)
• A Mining Remediation Authority abandonment plan (SWR1467) titled 'Glynmoch' records the Red Vein; the catalogue entry gives no location, and another Glynmoch (with Abergorky, in the Rhondda) also appears in the catalogue. (uncertain)

Golconda Mine Derbyshire

• Closure is generally reported as 1953, but a BGS mine-plan catalogue record separately gives 1985 as the plan's abandonment year — the two figures are not reconciled by any source found. (disputed)

Goldsborough Ironstone Mine North Yorkshire

• The ironstone at Kettleness was worked at two sites. Between 1838 and 1857 stone was won directly from the cliffs and beach and loaded onto ships in the bay, which was a hazardous operation, and shipped to the Wylam furnaces of Losh, Wilson and Bell. The other mine was west of the hamlet and operated between 1910 and 1915, the ironstone being forwarded to Skinningrove ironworks by rail. (uncertain)

Govan Colliery Glasgow

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Govan' (catalogue 7771, Upper Upper, dated 1923); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Graigola Colliery Neath Port Talbot

• Grace's Guide's independent record of the Graigola Merthyr Co (of Cambrian Place, Swansea, formed by Thomas Cory and Frank Yeo in 1879) confirms it as a real, substantial colliery-proprietor firm operating in the same Pontardawe district under the closely related "Graigola" name, though it names the company's acquisition by D.R. Llewellyn in 1918 rather than Graigola Colliery's own Benson and Smith/Graigola Colliery Company/Llwyndu succession — the two accounts are not claimed to describe identical ownership. (uncertain)

Grassmoor Colliery Derbyshire

• One account has the colliery remaining in production until at least 1961, working the Tupton, First and Second Piper and Deep Hard seams from the mid 1950s. (uncertain)

Great Dowgas Mine Cornwall

• Great Dowgas Mine is first recorded selling a small quantity of black tin around 1719; no earlier production figures survive, and the mine was reworked repeatedly, without great success, until 1913. (uncertain)

Great Work Mine Cornwall

• Great Work had opened by 1538. By 1584 the mine is recorded as employing at least 300 people with annual profits of around £1000 (Aslet, 2010). A higher, uncited figure of over 3,000 workers for the same late-16th-century period appears on some tourism-oriented sites (gooseygoo.co.uk, a Geograph photo caption) but is not independently corroborated and is treated cautiously here. (disputed)
• In 1930 the mine closed with some miners continuing to work above adit level; it was de-watered in the mid-1930s in an attempt to reopen it, and closed permanently in 1939 per Wikipedia. A more detailed account gives the final attempt as Great Work Tin Mines Ltd from 1935, de-watering the Deerpark shaft before abandoning it and allowing the lower workings to flood again, with work stopping for the last time in 1938. Both accounts describe the same closing episode; the exact final year is not fully reconciled between them. (disputed)
• Ownership of the mine passed from the Godolphin family to the Duke of Leeds in 1785; the mine's principal shaft, Leeds shaft, takes its name from this change of proprietor. (uncertain)
• The mine closed in 1793 as the price of tin fell, before being revived in 1810 as a major copper producer. (uncertain)
• The mine was worked again as Old Great Works between 1890 and 1902, as South West Cornwall Mines from 1907 to 1912, and from 1927 alongside neighbouring Wheal Reeth for about ten years. (uncertain)
• Mining engineer W. J. Henwood recorded in 1843 that where the Wheal Breage lode passed from granite into the surrounding greenstone (killas), the tin ore it carried disappeared instantly — a specific, documented illustration of the tin mineralisation being concentrated within the granite host. (uncertain)

Great Wyrley Colliery Staffordshire

• The Great Wyrley Colliery Company was in operation between at least 1872 and 1924 (VCH); the museum dates the colliery 1806 to August 1949 and the mining society's timeline has the Great Wyrley pit closing in 1925. (disputed)

Greenrigg Colliery West Lothian

• A local history has the colliery, owned by the Loganlea Coal Company, taken over by United Collieries in 1905 rather than 1902. (disputed)
• Clay from the pit went to the Etna brickworks, placed at Armadale by Canmore and at Bathgate by the local account. (disputed)

Greenrigg Pit West Lothian

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Greenrigg' (catalogue S335, Mill, dated 1960); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Greenside Mine Cumbria

• Some accounts place mining at Greenside as early as 1690, but no documentary evidence for a working this early has been produced; the earliest confirmed reference is a legal brief from 1799. (uncertain)

Greetwell Ironstone Mines Lincolnshire

• J. D. Kendall's Geological Survey memoir 'The Iron Ores of Great Britain' (1893) gives 1873 for the earliest workings at Greetwell, without fixing their location; Tim Hudson, following Eric Tonks, suggests that date may belong to Monks Abbey and puts the start at Greetwell itself at 1878. (disputed)
• The county Historic Environment Record, citing Stewart Squires's 2010 study, dates the ironstone quarries east of Lincoln to 1875 and Greetwell Mine to 1879. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Greetwell' (catalogue OM13147, Ironstone, dated 1881); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Groverake Mine County Durham

• Groverake was worked for ironstone from 1819 before later becoming a lead, then fluorspar, mine. (uncertain)
• As a lead mine Groverake produced only about 6,498 tons of lead concentrates between 1818 and 1883. (uncertain)
• From 1983 Groverake was connected underground to Frazer's Hush mine by a 2 ft gauge battery-electric railway. (uncertain)
• Durham County Council served a building preservation notice on the winding house in 2013; the site was vandalised and stripped by scrap thieves in 2015 before the headstocks were secured by a community campaign in 2017. (uncertain)

Gunnislake Clitters Mine Cornwall

• Cornwall Calling gives the mine as worked from 1820 to 1919, first by an adit from the valley side and later by shafts; the Durham Mining Museum records it as opened in 1860 and closed in 1889, which matches the life of the Gunnislake Clitters Mining Co. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Gunnislake Clitters' (catalogue OMR63A, Tin Copper And Arsenic Ores, dated 1889); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Gurney Slade Quarry Somerset

• Wikipedia says work began at the quarry in the mid eighteenth century; the British Geological Survey's history of the East Mendip quarries says it began on a small scale in the mid nineteenth century, with some accounts giving Francis Flower's lime-burning here as starting in 1873. (disputed)

Gurnos Colliery Powys

• It abandoned the Four Feet seam in November 1922 and the Peacock or Brass seam in August 1928, when it closed, and was retained for pumping until 1944. (disputed)
• It employed 250 men in 1930 and 1934 and closed prior to 1947. (disputed)

Gwaith Yr Afon Mine Ceredigion

• Gwaith Yr Afon's working period (1853-1878) overlaps the reopening of the neighbouring Cwmsymlog sett as the East Darren Mine from 1850, worked until 1882 -- the two are likely companion east/west workings of the same mid-19th-century revival of the Darren-Cwmsymlog fault system, though no source names a specific operating company for Gwaith Yr Afon itself. (uncertain)

Gwaun Cae Gurwen Colliery Neath Port Talbot

• Richard Hopkin sank the first pit, the Old Pit, in 1837, to 175 yards. (disputed)
• The first pit, elliptical and 16 feet by 8, was sunk to 160.95 metres in 1837 by Roger Hopkin, with a second shaft in 1847. (disputed)
• The Old Pit was sunk in 1837 by Charles Morgan, a local landowner. (disputed)
• The Maerdy Pit was closed by the NCB in 1948. (disputed)
• The Maerdy Pit was closed in January 1958. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Gwaun Cae Gurwen' (catalogue CRO46, Peacock, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Gwendraeth Colliery Carmarthenshire

• Twenty-six men and boys died in the inundation of 10 May 1852. Contemporary reporting puts 27 on the night shift with a single survivor, David Evans, which reconciles with the figure of 26 dead; some later summaries instead give 27 lives lost, apparently by counting the whole shift as fatalities. (disputed)
• The colliery reopened after the disaster and was listed as working in 1869, closing at some point during the 1870s. No source located gives a precise closure date. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Gwendraeth' (catalogue 9571, Carway Fawr, dated 1928); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Habergham Colliery Lancashire

• The museum dates the colliery 1854–1941; the Burnley Coalfield account has production from the Arley at 218 m beginning in 1870 after two years' development, and closure in 1941 through a shortage of manpower. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Habergham' (catalogue 12613, Arley Yard, Blindstone, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Hafna Mine Conwy

• The Geograph record gives the mill complex an original construction date of 1879, with working ceasing around 1915. (disputed)
• The Gwydyr Forest record describes the stepped mill as dating from 1889–1905, of French design, and powered successively by water, steam and electricity. (disputed)

Haig Colliery Cumbria

• A further explosion on 12 February 1928 killed 13 men at Haig Colliery. (uncertain)

Hallenbeagle Mine Cornwall

• Sources disagree on the pumping engine's exact size: Explore Cornwall records it as a 60-inch engine, while a Geograph caption for the same building notes that sources differ between 60 and 70 inches. (disputed)
• A smaller 22-inch whim engine also worked the mine and was moved on to Dooneen Mine in Ireland by 1872. Explore Cornwall places this engine at Reed's Shaft alongside the pumping engine; Cornish Mine Images instead places it at a separate Doctor's Shaft. (disputed)
• Just before the 1870s Hallenbeagle was reported worked jointly again, this time with East Downs Mine — reported by Explore Cornwall only, and not independently corroborated in this research pass. (uncertain)

Hangman's Wood Deneholes Essex

• The shafts were sometimes known as 'Cunobeline's gold mines', a folk name linking them to the Iron Age British king Cunobelinus, though no evidence supports this origin. (disputed)

Hardshins Lead Mine Cumbria

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Hardshins' (catalogue OM2525, Lead Ore, dated 1890); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Harraton Colliery Tyne and Wear

• Coal was first recorded as produced at Harraton Colliery in 1594. (uncertain)
• During the English Civil War, with the Tyne coal trade halted and the Port of Sunderland supplying London, Harraton Colliery came under the control of Scottish soldiers aligned to the Parliamentarian cause and was of some significance in that trade. (uncertain)
• Large-scale mining at the colliery started in 1794. The Durham Mining Museum records the colliery as working before that year. (uncertain)
• The colliery was known locally as the Cotia pit, the name coming from its Nova Scotia pit, which the area became known as because of the number of Scots who worked there. (uncertain)
• The Imperial Gazetteer of England and Wales for 1870-72 recorded that coal was extensively worked at Harraton but that the majority of the coal pits were exhausted. (uncertain)
• The pit closed in May 1965, with many of its miners migrating to the modern pits in Nottinghamshire. (uncertain)

Harry Crofts Colliery South Yorkshire

• The colliery closed in 1930. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Harrycrofts Colliery' (catalogue SFE189, Surface, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Hartington Colliery Derbyshire

• The New Hollingwood Deep Winning was sunk in 1858, a single 12-foot shaft 218 yards to the Deep Soft divided by a wooden brattice into downcast and upcast halves with an underground ventilating furnace. (disputed)
• A list of the Staveley collieries dates New Hollingwood, or Hartington Silkstone, to 1855, and notes that housing was built on the site and later demolished. (disputed)

Hartside Mine Cumbria

• The BGS mine-plans catalogue holds a BGS plan titled 'Hartside Mines' (catalogue SP2080, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Haunchwood Colliery Warwickshire

• The sinking date of Tunnel Colliery is given variously as 1891 by Keith Turton, 1892 by Our Warwickshire and 1894 by Warwickshire Railways. By 1895 it employed 817 men underground. (disputed)
• The original Nowell’s pit is recorded as closing in 1914 by one contributor to Warwickshire Railways and as ceasing coal winding on 7 July 1925 by another on the same page; both agree that submersible pumps were then fitted in its shafts to keep the Tunnel Pit’s seams free of water. (disputed)
• Tunnel Colliery closed on 25 March 1967 according to Warwickshire Railways and Our Warwickshire; Keith Turton, on the same Warwickshire Railways page, gives 1970. (disputed)

Haywood Colliery Gloucestershire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Haywood' (catalogue 8656, Under, dated 1926); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Hazard Mine Derbyshire

• The Historic Environment Record says the mine was worked to 600 ft, a hundred fathoms, though the engine shaft is only 350 ft deep. Derbyshire Heritage says the shaft had a depth of nearly 700 ft in the 1830s. Peak District Caving records the engine shaft as 79 m deep. (disputed)

Hazlerigg Colliery Tyne and Wear

• The Durham Mining Museum gives the closing date as 25 April 1964. (disputed)
• The Tyne and Wear Historic Environment Record gives the closing date as 25 November 1964. (disputed)

Healeyfield Mine County Durham

• The BGS mine-plans catalogue holds a BGS plan titled 'Healeyfield Mine.' (catalogue SP2087, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Hemerdon Mine Devon

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Hemerdon' (catalogue OM15351, Tin, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Hendre Mine Flintshire

• Cadw's listing puts the Taylor's Shaft engine house at probably 1896, the date on the adjacent boiler stack. A 2006 field note instead describes it as built during the First World War to revive the lead mines. (disputed)

Hendreforgan Colliery Neath Port Talbot

• NMRS gives the colliery, also called Cox's, as opened in 1817. (disputed)
• The colliery closed around 1924 and may have been integrated with the nearby Coedffalde colliery, under whose name it appears on maps from 1918. (uncertain)

Herrington Colliery Tyne and Wear

• The colliery is often called Philadelphia Colliery after the neighbouring settlement of Philadelphia, which gave its name to the Lambton Railway's locomotive works serving the Lambton collieries. (uncertain)

Hickleton Main Colliery South Yorkshire

• Accounts differ: the colliery is described as working from 1892 to 1988, while Goldthorpe and Hickleton were merged into one unit from 1 January 1986 and production ceased on 4 February 1994. (disputed)

High Sedling Mine County Durham

• The BGS mine-plans catalogue holds a BGS plan titled 'High Sedling Mine' (catalogue MP18748, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Higher Pitts Mine Somerset

• The Somerset Manganese and Iron Ore Co. was formed in 1890 to work Higher Pitts Mine, under manager Willcox, but closed within a few years -- sources differ on whether work ceased in 1891 or the company closed the mine in 1893. (disputed)

Holditch Colliery Staffordshire

• Staffordshire Past Track dates the colliery 1912–1989; the Wikipedia account says it closed in 1990, three years after the end of the year-long miners’ strike, with many of its miners transferring to Silverdale Colliery. (disputed)

Hollinswood Colliery Staffordshire

• The gazetteer gives Edwards's dates as 1853 to 1912; Wikipedia, following the Encyclopaedia Britannica, gives his birth as 10 April 1852 at Talk-o'-the-Hill. A birth in April 1852 fits the gazetteer's 'aged 9 in 1861'; a birth in 1853 does not. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Hollinswood' (catalogue 12169, Four Feet, dated 1937); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Holly Bank Colliery Staffordshire

• The Willenhall History Society states that Essington Wood went into liquidation in 1895 and the Holly Bank Trust Company was set up; the Durham Mining Museum gives 1895 as the colliery's opening. (disputed)
• The Durham Mining Museum lists Holly Bank as producing household and manufacturing coal in 1947, but the brick historian reads the same records as showing no men underground at nationalisation. (disputed)

Holmbush Mine Cornwall

• The BGS mine-plans catalogue holds a BGS plan titled 'Holmbush' (catalogue MP24157, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Holmewood Colliery Derbyshire

• The Durham Mining Museum gives the sinking as started in 1870. (disputed)
• The colliery closed in 1968, after which the area was opencast; one local account gives the closure as 1966. (disputed)

Holyfield Mine Cumbria

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Holyfield' (catalogue OM15115, Lead Ore, dated 1872); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Home Farm Colliery, Hamilton South Lanarkshire

• The museum gives 1870 to 1925; Moore's 1877 report says worked for about ten years and The Times said since 1864. (disputed)

Honister Slate Mine Cumbria

• The mine closed in the 1980s under Alfred McAlpine ownership after a protracted decline; sources give the year as both 1986 and 1989. (disputed)

Hook Colliery Pembrokeshire

• Hook's smokeless anthracite was reputedly favoured by Queen Victoria and used in royal palaces. (uncertain)

Hooten Wheals Devon

• Sources disagree on closure -- one Historic Environment Record states the lease was terminated in 1896, another account has activity continuing a few years longer before a 1920 storm ended it. (disputed)

Hopewell Colliery Gloucestershire

• The freemining right dates to the reign of Edward I and is said to have been granted in recognition of the miners' military service, possibly at the recapture of Berwick-upon-Tweed — an origin that remains traditional rather than documented. (uncertain)

Hostingley Colliery West Yorkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Hostingley' (catalogue GCR107, Flockton Thin (Or Mill Bank Bed), dated 1873); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Hough Hole Colliery Cheshire

• The mine was officially abandoned at the beginning of 1925 as effectively exhausted; The Story of Rainow, drawing on the recollections of Frederick Vare, the last man to work in it, says working ended abruptly in 1926 when black damp was found. Working may have restarted during the 1926 national strike, as it appears to have done at other small mines in the district. (disputed)

Huntcliffe Mine North Yorkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Huntcliffe' (catalogue OM4990, Ironstone Main, dated 1906); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Hyde Colliery Greater Manchester

• The colliery manager's own report of about the same date gives the downcast and winding shaft as 274 yards deep and the upcast as 220 yards. (disputed)

Ifton Colliery Shropshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Ifton' (catalogue NW567, Powell, dated 1965); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

International Colliery, Abercrave Powys

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'International, Abercrave' (catalogue SW198, Peacock, dated 1954); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Ireland Colliery Derbyshire

• The Durham Mining Museum and a 1967 NCB leaflet give the sinking as 1858, which is the date of the New Hollingwood Deep Winning rather than of the Ireland shaft. (disputed)
• The colliery closed as an independent pit in 1986, when it is said to have been absorbed into the Markham complex as Markham No. 5. (uncertain)

Irthlingborough Ironstone Mine Northamptonshire

• The Coal Authority's three-sheet abandonment plan for Irthlingborough (OM15242) gives an abandonment date of 30 September 1965. (disputed)
• The Richard Thomas and Baldwins plan of the Northampton Sands ironstone mine at Irthlingborough (KP23319) is catalogued as abandoned in 1966. (disputed)
• A 2010 forum report on other Northamptonshire ironstone mines, near Kettering, describes accessible workings retaining hand-drilled faces, abandoned tools and rail-and-brick roof supports, and records oxygen at 17 per cent in an adjacent mine, falling further from the entrance. (uncertain)

Jackfield Colliery Shropshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Jackfield' (catalogue 1025, Rowhurst, New Mine, Bungilow, Winghay, Burnwood, Little Mine Ironstone, dated 1879); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Jamage Colliery Staffordshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Jamage' (catalogue 17315, Spoil Tip (Ref.Nos. 15/28/1 & 15/28/2), undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Jenny Gray Colliery Fife

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Jenny Gray' (catalogue S4413, Lochgelly Parrot, dated 1855); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Kelty Colliery Fife

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Kelty' (catalogue 7898, Kelty Main, dated 1895); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Killan Colliery Swansea

• The memorial names the men who died on 27 November 1924 as Wilfred John, seventeen; Willie Goulding, twenty-two; Charles Evans, thirty; Archie Davis, twenty-eight; and Phil Godbeer, thirty-two. The Inspector of Mines' report of 1924 names them as Wilfrid John, fifteen; James Goulding, twenty-one; Charles Evans, thirty-nine; Archie Davies, twenty-eight; and Philip Godbeer, thirty-two. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Killan' (catalogue SWR2795, Penclawdd, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Killhope Lead Mine County Durham

• Total output from the Killhope workings before 1818 alone is estimated to have exceeded 60,000 tonnes of lead concentrate. (uncertain)

Kilroot Salt Mine County Antrim

• The workings extend over more than 350 hectares at over 400 m below ground. (uncertain)
• The surface site occupies the former Kilroot coastal artillery battery, decommissioned in 1956; the company operated from the fort's converted buildings before a purpose-built operations building was constructed. (uncertain)

Kimmeridge Oil Shale Workings Dorset

• Sources disagree on how far Clavell’s ventures actually operated: the Royal Commission inventory states that the alum, salt and glass enterprises "came to nothing", while contemporary accounts quoted by Parkins describe the works in production, including a 1620 Survey of Dorsetshire description of men labouring about the glasshouse fires. (disputed)
• The identity of the shaft sunk after 1883 is disputed: recent histories, following Ian West’s summary, call it the Manfield Shaft, while the Museum of the Scottish Shale Oil Industry holds that this is an error arising from a misreading of Strahan’s account of the Manfield shale pit at Portesham. (disputed)

Kingseat Colliery Fife

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Kingseat' (catalogue S3030, Diamond & Five Feet, dated 1937); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Kirkmeadow Mine Derbyshire

• The shaft's own name is not confirmed by documentary evidence; it is known locally from the field enclosure it sits within, Kirkmeadow, and references to a 'Kirkmeadow Shaft' describe one housing an engine in the 1700s. (uncertain)

Knockterra Colliery East Ayrshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Knockterra' (catalogue 6187, Ell, dated 1914); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Lady Windsor Colliery Rhondda Cynon Taf

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Lady Windsor' (catalogue SWA1128, Four Feet, dated 1957); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Ladywash Mine Derbyshire

• A 2024 exploration report states that management informed the workforce in February 1979 that Ladywash was to close, citing falling world fluorspar prices alongside rising costs 'in light of recent fatalities which led to the need for increased investment in health and safety' — no further detail on these fatalities (names, dates or number) has yet been located. (uncertain)

Landshipping Colliery Pembrokeshire

• Coflein records the shaft as 67 feet deep; Welsh Coal Mines gives 67 yards. (disputed)

Langley Barony Mine Northumberland

• Thomas Bewick obtained a lease of the minerals in Langley Barony in 1868 and was later joined by local businessmen to form Bewick and Partners; output rose from 30 tons in 1873 to 4,760 tons by 1882, then declined to 230 tons by 1893 when the mine closed. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Langley Barony' (catalogue OM15348, Lead Ores, dated 1943); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Langness Mine Isle of Man

• Mining for metals on the Isle of Man probably began as early as the Bronze Age, with early sites identified at Langness and Bradda Head, where copper could be seen outcropping in the cliffs. (uncertain)

Lead Mines Clough Lancashire

• Archaeological and isotopic evidence indicates lead was being extracted on Anglezarke Moor c.680-1000 AD, most likely from the veins later worked at Lead Mines Clough, though later mining has destroyed most direct physical evidence of this early activity. (uncertain)

Leadhills South Lanarkshire

• One account states the last shaft at Leadhills closed in 1938; another describes mining across the wider Leadhills–Wanlockhead district continuing, on a reduced basis, into the 1950s. (disputed)
• A mining disaster in 1817 killed seven miners from noxious fumes; some accounts note ambiguity over whether the rescue attempt itself contributed to the death toll. (uncertain)
• Gold mined at Leadhills between 1538 and 1542 was reportedly used to make crowns presented to James V and his queen, valued at the time at around £100,000. (uncertain)

Ledston Luck Colliery West Yorkshire

• The Durham Mining Museum gives 1909 as the opening, records 98 people employed in 1910 with the note 'Sinking', and has no returns at all before then; Engole's account has the sinking begun in 1909 with Lady Wheler cutting the first sod. (disputed)
• Both of the exploration accounts read for this record say the pit was sunk in the 1870s, and one adds that it later formed part of the super-pit of interlinked workings around Selby. Neither cites a source and the wording is close enough between them to suggest one copied the other. (disputed)

Leeswood Green Colliery Flintshire

• The Annual Register says notice of a reduction for turning out dirty cannel took effect on the 17th and that Young was ejected on the 19th; the Leeswood Community account says the notice was posted on 1 May, that the reduction was due to start on 17 May when three hundred men did not turn up, and that he was confronted two days later. (disputed)

Levant Mine Cornwall

• Documented mining at Levant dates from April 1787; claims that the site was worked as early as the Roman period (around 200 AD) are not backed by firm evidence. (uncertain)
• Over its working life Levant produced in excess of 130,000 tons of copper and 24,000 tons of tin, along with substantial arsenic. (uncertain)
• The company was restructured as Levant Tin Mines Limited in 1920 under Colonel F. F. Oats. (uncertain)
• Seawater was found to have broken into the abandoned workings at the 40 fathom level; two sealing attempts in the 1950s were needed before the breach was closed in the 1960s. (uncertain)
• Geevor reopened Levant's undersea ground in November 1980 by way of an inclined shaft driven at about 25 degrees, working it until Geevor itself closed. (uncertain)

Limeylands Colliery East Lothian

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Limeylands' (catalogue 9539, Parrot, dated 1928); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Linby Colliery Nottinghamshire

• Sources disagree on when Linby began work: the Durham Mining Museum gives a sinking in the late 1860s, the Nottinghamshire Historic Environment Record an opening in 1875, and the memorial plaque on the site 1873. (disputed)

Lintzgarth Mine County Durham

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Lintzgarth' (catalogue OM11734, Silica And Iron Ore, dated 1930); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Little Garth Mine Cardiff

• It is estimated that some 700,000 tons of haematite were removed by hand over the lifetime of the mine, with some estimates as high as 1,000,000 tons. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Garth' (catalogue OM1636, Iron Ore, dated 1884); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Llanbradach Colliery Caerphilly

• Welsh Coal Mines records 2,330 men employed at the outbreak of the First World War. A folklore account gives 2,832 by 1913; the two are not reconciled here. (uncertain)

Llanbradach Quarry Caerphilly

• A photograph of 1905 in the National Library of Wales's Martin Ridley Collection shows the quarries in work. No source located names an operator or gives an opening or closure date. (uncertain)

Llanerch Colliery Torfaen

• The colliery began about 1830 as Cwmnantddu, a level working the Tillery seam; the earliest traced mention is a county-court case of December 1833. (uncertain)
• The Varteg Iron and Coal Company sank new shafts about 1853, each 253 yards deep, with 45-foot pitch-pine headgear and furnace ventilation. (uncertain)
• Llanerch provided the downcast ventilation for the neighbouring Blaenserchan colliery until that pit developed its own downcast shaft in 1913. (uncertain)
• Llanerch employed 913 men in 1923, producing from the Elled, Big Vein, Three Quarters, Old Coal and Black Vein seams, and 325 men by 1938. (uncertain)

Llanharry Iron Mine Rhondda Cynon Taf

• The mine closed in 1976. (disputed)
• The closure is given as 1975 elsewhere. (disputed)

Llay Main Colliery Wrexham

• At sinking the colliery was described as the deepest pit in Europe, at a depth of about 730 metres. (disputed)

Llechwedd Slate Caverns Gwynedd

• According to the traditional account, unpaid workers continued searching after funding ran out and struck the rich 'Old Merioneth Vein' within weeks, securing the quarry's future. (disputed)

Lletty Shenkin Colliery Rhondda Cynon Taf

• Welsh Coal Mines gives 1872 for the purchase by Burnyeat, Brown and Company; a Cynon valley local history gives 1874, and says the house was bought with the colliery. (disputed)
• The Durham Mining Museum gives 1913 as the closing date, although its own employment returns and fatality records for the colliery continue to 1915. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Lletty Shenkin' (catalogue R379, Upper Four Feet, dated 1849); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Lluest Colliery Bridgend

• The colliery is mentioned in a list dated 1880 under the Lluest Coal Co. Ltd, and by 1887 was owned by the Abernant Colliery Company and managed by H. Harries. (uncertain)
• The colliery worked the No. 3 Rhondda seam at a thickness of between twenty-two and forty-two inches. (uncertain)
• The Inspector of Mines' list for 1896 records 154 men employed at this house-coal colliery. (uncertain)
• Production ceased at the colliery in 1902. (uncertain)

Llwyngwern Quarry Powys

• Wikipedia dates the experiment in green living on the site to 1972; the Royal Commission's record says the Centre for Alternative Technology was founded in 1973. (disputed)

Lochgelly Colliery Fife

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Lochgelly' (catalogue 3188, Five Feet, dated 1894); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Lodge Syke Mine County Durham

• The mine's two levels, Low and High, were both accessed from the Hudeshope valley and extended to connect with workings from the Eggleston valley, the Lodgesike-Manorgill vein being the primary target of exploitation. (uncertain)

Loftus Mine North Yorkshire

• Loftus Mine's output peaked at 654,000 tons of ironstone in 1881, and by 1896 employed 781 people, 676 of them underground. (uncertain)
• The mine's North Drift was used as an air-raid shelter for the Skinningrove steelworks during Zeppelin raids in the First World War. (uncertain)

Long Meg Mine Cumbria

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Long Meg' (catalogue OM6294, Gypsum Or Alabaster, dated 1914); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Longacres Mine North Yorkshire

• An outfall believed to come from Longacres discharges bright orange water into Holme Beck, and minewater first appeared in Saltburn Gill on 18 May 1999, described locally as thirty-five years after the mine closed. (uncertain)

Longcliffe Quarry Leicestershire

• The quarry was run by ARC and later Hanson Aggregates/Midland Quarry Products, per sources no more recent than around 2011; current operatorship is not confirmed. (uncertain)

Longhoughton Quarry Northumberland

• A lease of 1896 between the Duke of Northumberland's Alnwick Castle Estate and H. G. Prowde Ltd covered the 'Longhoughton Whinstone and Limestone Quarry', with a further lease to the same company in 1919, while the Northumberland Whinstone Company is recorded working here from 1887. The source states that matters are not completely clear and suggests the Prowde leases may refer to a new quarry opened east of the original. (disputed)

Loughrigg Fell Slate Quarry Cumbria

• Rydal Cave, on the northern slopes of Loughrigg Fell above Rydal Water, is a former slate mine — originally Loughrigg Quarry — abandoned in the 19th century and now a large chamber with a flooded floor. (uncertain)

Loveston Colliery Pembrokeshire

• Contemporary newspaper reporting described the colliery as owned by a French company, while Welsh Coal Mines records the operator as the Loveston Colliery Co. Ltd. The two have not been reconciled. (disputed)

Lumpsey Mine North Yorkshire

• The Victoria County History states that Lumpsey mine, in the northern part of Kilton near the railway, was opened in 1880. (disputed)
• Bulmer's directory of 1890 states that Lumpsey Mines were commenced in 1882, and the Durham Mining Museum's first return for the mine is for that year. (disputed)

Lundhill Colliery South Yorkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Lundhill' (catalogue 3280, Abdy, Winter,Furnace, dated 1895); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Lynemouth Colliery Northumberland

• Wikipedia records 1,734 people employed in 1960. The split it gives — 1,390 above ground and 344 below — is implausible for a working colliery and is not repeated here as fact. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Lynemouth Colliery' (catalogue 17948, Ellington Combine, dated 2005); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Maenofferen Quarry Gwynedd

• Underground production ended in November 1999 according to Wikipedia, Coflein and TheTimeChamber, but November 1998 according to Festipedia; the discrepancy is not resolved by any source consulted. (disputed)

Maes Marchog Colliery Neath Port Talbot

• Already working before 1743; Humphry Mackworth opened the Waen-Marchog colliery in 1791 (one account instead gives Herbert Mackworth and 1793), driving into the Nine-Feet (Big Vein) seam near its outcrop. (disputed)

Magpie Mine Derbyshire

• Most accounts give final closure as 1958; one source instead gives 1954 for the end of the post-war Waihi Investment and Development Company operation. (disputed)
• Magpie Mine produced 800 tons of lead in 1827, a site record that reportedly stood unbroken until 1871. (uncertain)
• A 2018 report on the surface remains notes that Magpie Mine's sough still discharges an estimated four to six million gallons of water a day, and that water is visible roughly 528 feet down the main shaft. (uncertain)

Mainsforth Colliery County Durham

• Two shafts were sunk in 1873 to 270 ft to the Five Quarter seam; the mine was abandoned by 1877 and the shafts used as a rubbish dump. The cause has been attributed both to the slack coal trade after the Franco-Prussian war and to an inundation of the pit. (uncertain)

Maltby Colliery South Yorkshire

• An explosion in August 1911 killed three colliers. (uncertain)

Mandale Mine Derbyshire

• A July 2016 report notes that Mandale Mine's main underground entrances were locked at the time of the visit, limiting exploration to the surface remains including the engine house, sough and Bateman's House. (uncertain)
• A visit in June 2026 found the incline level dry, with good headroom, open passages and visible mineralisation; the aqueduct level narrow, showing older stoping, and obstructed by fallen timber and boulders; and the sough dry on the day and lined with fine stonework, though a collapse stops progress a short way in. On the surface the engine house, the water course that served the waterwheel and a stone bath-like feature were all still standing. (uncertain)
• The surviving accessible workings run to roughly 400 metres, reached through four separate level entrances — Incline, Aqueduct, Upper and Sough — with the Forefield Shaft sealed. The sough lining beyond the foot of that shaft is badly collapsed, and parts of the mine hold unstable boulder ground and fluctuating water levels. (uncertain)

Mapperley Colliery Derbyshire

• The museum's page heads the colliery 'Duckmanton, nr Chesterfield' and carries a Markham description, but its grid reference SK423433 and every other source place it at Mapperley near Ilkeston. (disputed)

Maritime Colliery Rhondda Cynon Taf

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Maritime' (catalogue SWA767, Six Feet (Four Feet)., dated 1958); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Mauricewood Colliery Midlothian

• The pit was sunk by the Shotts Iron Company in the 1870s (reported as c.1875), initially for ironstone before working coal. (uncertain)

McLaren Colliery Caerphilly

• Abertysswg came into being between 1895 and 1900 through the industrialisation brought by the development of the colliery, the first shaft of which was sunk in 1897. (uncertain)
• The pit opened in 1897 and was originally called Pwll Llaca Pit; the McLaren Colliery later re-used the shaft, and it was eventually renamed Abertysswg. (uncertain)
• The pit produced steam coal for the steel industry and closed in 1969. (uncertain)
• An explosion at the colliery on 3 September 1902 killed seventeen men; the death roll names them with their ages and addresses. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Mclaren' (catalogue SWR953, No. 3 Pit, dated 1957); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Meiklehill Colliery East Dunbartonshire

• The Durham Mining Museum lists six owners in succession: James Gairdner, James Gairdner and Sons, the Meiklehill Coal Co., James Wood Ltd, United Collieries Ltd and the Woodilee Coal and Coke Co. Ltd. It gives no dates for any of them, and none has been found elsewhere. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Meiklehill' (catalogue 8662, Main, dated 1926); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Melton Bottom Chalk Pit East Riding of Yorkshire

• The quarry has been running for just over a century and supplies high quality chalk to an adjacent production facility making fillers, powders and extenders for chemical and industrial applications, around 300,000 tonnes being extracted a year; it was owned by Omya and producing chalk whiting as of 2012. These figures come from search summaries rather than a fetched page and should be confirmed. (uncertain)

Merrybent Copper Mine North Yorkshire

• The BGS mine-plans catalogue holds a BGS plan titled 'Merrybent Mines' (catalogue KP13415, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Michael Colliery Fife

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Michael' (catalogue S611, Wemyss Parrot, dated 1958); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Middle Duffryn Colliery Rhondda Cynon Taf

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Middle Duffryn' (catalogue SFE44, Surface, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Milldam Mine Derbyshire

• Milldam was the last working fluorspar mine in Derbyshire. (uncertain)

Milnwood Colliery North Lanarkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Milnwood' (catalogue 1718, Main, dated 1884); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Minera Lead Mines Wrexham

• Roman-period working of the field is often claimed but has no supporting archaeological evidence. (disputed)
• One observational source dates the effective abandonment to around 1909, ahead of the commonly cited 1914 closure. (disputed)
• Meadow Shaft and Taylors Shaft each reached roughly 300-400m (c. 400 yards) deep. (uncertain)

Minnie Pit Staffordshire

• Wikipedia gives the pit as opened in 1881; the North Staffordshire Mining Group dates the start of sinking to April 1883, water and quicksand having hampered the work in 1882. (disputed)

Moelwyn Quarry Gwynedd

• The quarry ran basic literacy classes for its workforce in the 1860s, which were, according to a sourced account, visited by the sitting Prime Minister, Lord Palmerston. (uncertain)

Moorfield Colliery Lancashire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Moorfield' (catalogue 10399, Upper Mountain, dated 1930); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Moresby Colliery Cumbria

• The Walkmill pit was sunk and raising coal by the end of 1878, and is the pit known both as Moresby Colliery and as Walkmill Colliery. The archaeological assessment dates the sinking to 1879, following Oliver Wood’s history of the West Cumberland industry. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Moresby' (catalogue NC177, Bannock, China & Main, Six Quarters, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Morfa Colliery Neath Port Talbot

• The official returns date the colliery's opening to 1847 and its closure to October 1913, with Abbot Pit and Grange Pit, Vivian and Sons as owner, coking, household and manufacturing coal from the Cribbwr and Four Feet seams, and employment of 315 in 1894, 325 in 1896, 386 in 1900, 320 in 1905 and 199 in 1910. (disputed)

Mostyn Colliery Flintshire

• Accounts differ on how long coal had been worked when the 1884 flood ended it: over 620 years by one reckoning and 823 years by another, the difference resting on which thirteenth-century start date is taken. (disputed)

Mountsorrel Quarry Leicestershire

• Roman-era activity is traditionally associated with the site: a villa reputedly stood on Broad Hill, and 19th-century quarrying there uncovered artefacts including a preserved wooden bucket. (uncertain)

Muirshiel Barytes Mine Renfrewshire

• Barytes mining at Muirshiel was dangerous work, with many men killed or badly injured over the mine's life by rock falls, accidents with explosives, and accidents travelling to and from the remote site, though no single incident is documented in enough detail to stand as a discrete disaster record. (uncertain)

Nailstone Colliery Leicestershire

• J. J. Ellis owned the colliery in 1866 and sold out in 1875; it closed in 1876, was working again under new ownership by 1883, and was taken over by the Nailstone Colliery Company when that owner died in 1887. Whether Ellis originated the colliery is not certainly known. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Nailstone' (catalogue EM903, Upper Main, dated 1940); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Nangiles Mine Cornwall

• By 1864 the mine had reached 117 fathoms below adit and was equipped with a 30-inch stamps engine and a winding engine in addition to the pumping engine; a separate 36-inch stamps engine was installed in 1871 by the Welsh Gold Mining Company, driving 84 stamp heads, and was sold on to West Condurrow in 1891. (uncertain)
• The ground was investigated and worked for tin again by the Wheal Jane group in 1969–79 and 1980–91, alongside Wheal Jane's own much larger contemporary operation nearby. (uncertain)

Nant Gwrtheyrn Quarries Gwynedd

• Nant Gwrtheyrn's own history dates the first sett quarry in the valley to 1851 under Hugh Owen of Anglesey, with the Liverpool firm Kneeshaw and Lupton taking control in 1861; other accounts give 1861 as the opening date and Kneeshaw and Lupton as the opener, while Coflein says only that modern quarrying started shortly after 1850. (uncertain)

Nant Hir Colliery Neath Port Talbot

• From 1994 owned by Ward Brothers; in 2003 owned by M. & W.A. Anthracite Ltd, when the mine received a £31,200 Government grant under the Coal Operating Aid Scheme (Welsh Coal Mines gives the grant as November 2003, NMRS as March 2003); ownership passed to Metal Innovations Ltd in 2008. (disputed)

Nantwen Colliery Merthyr Tydfil

• One account places closure in 1924 alongside the Bedlinog pits; NMRS's own manpower series instead reports Nantwen jointly with a mine called Danyderi from 1923 through to 1931, implying some working continued past 1924. (disputed)

Nenthead Mines Cumbria

• Modern mineral exploration, including boreholes drilled to around 1,640 ft in 2013, has identified potentially substantial untapped zinc deposits roughly 490 ft below the surface at Nenthead, though no new mining has resulted. (uncertain)
• A May 2009 report describes pony hoofprints and hobnail bootprints still visible in taped-off ground at Smallcleugh, an 1795 carving in the stonework, and tools left underground at Nenthead “almost as though the miners had left the day before.” (uncertain)

Nentsbury Mine Cumbria

• The BGS mine-plans catalogue holds a BGS plan titled 'Nentsbury Mine' (catalogue CT158, dated 1956); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Netherseal Colliery Derbyshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Netherseal' (catalogue 14339, Stockings, dated 1947); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Neumann's Mine Cheshire

• Neumann's Mine's roof collapsed -- most commonly dated to 1873, though other sources give 1877 -- creating Neumann's Flash; this is distinct from the 1880 'Great Subsidence' that created the separate, nearby Ashton's Flash. (disputed)

New Boston Colliery Merseyside

• Sunk about 1854 and lasting until 1910 (Wikipedia and Engole); the museum dates it 1880–1910 with two people pumping in 1910; the NMRS gives closure in 1907. (disputed)

New Hawne Colliery West Midlands

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Hawne' (catalogue 11705, Thick, dated 1897); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

New Stubbin Colliery South Yorkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Stubbin' (catalogue NE563, Whinmoor, dated 1965); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

New Tredegar Colliery Caerphilly

• 1,088 men were employed in 1896 and 1,156 by 1918. For 1923 Welsh Coal Mines gives 1,372 while the Durham Mining Museum's return gives 1,187. (disputed)
• The colliery was sunk by the Newport merchant Thomas Powell in 1853, with two shafts each 345 yards deep — one for winding, the other for ventilation and pumping. (uncertain)
• The Powell Duffryn Steam Coal Company took over the ownership in 1863 and added two more shafts, the last sunk in 1905. (uncertain)
• The pit was forced to close in 1929 when the side of the nearby mountain slid, badly damaging two of the shafts; the site was not cleared until 1965. (uncertain)

New Wernddu Colliery Neath Port Talbot

• NMRS lists New Wernddu under 'Clydach, Swansea Valley'; Coflein's grid reference places it in the Dyffryn Clydach area north of Neath instead. (disputed)
• The colliery employed 582 men in 1922 and closed in October 1922. (disputed)
• It probably closed in January 1929, when it abandoned the Graigola and Victoria seams. (disputed)
• A Mining Remediation Authority plan (R12055) for 'Wernddu and Wernddu New / Bryn Dewi' in the Four Feet (Victoria) (Ty Edmund) and Graigola seams is dated to abandonment in January 1927, a third date beside NMRS's October 1922 and January 1929. (disputed)

Newbattle Collieries Midlothian

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Newbattle' (catalogue S3825, All Seams, dated 1900); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Niddrie Colliery Midlothian

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Niddrie' (catalogue 9070, Peacocktail, dated 1926); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Nine Mile Point Colliery Caerphilly

• Sources disagree on the date of an earlier serious labour disturbance at the colliery: one places it in 1922 (colliery manager confronted over wage cuts, sixteen miners arrested), another in 1929 (several hundred villagers and miners involved in disorder over blackleg labour). Not resolved here as a single event. (disputed)

Norman's Quarry Dorset

• This archive's own account of the Purbeck marble quarries has Norman's sunk in the early twentieth century by the Norman family and worked until the Second World War; the Dorset Life account has the workings reopened in 1995 by the widow of the last quarryman, which implies working later than that. (disputed)

North Blaina Colliery Blaenau Gwent

• A Mining Remediation Authority abandonment plan (SWR3577) covers 'North Blaina, Milfrawn Pit, North Griffin Pit, Sun Pit' in the Yard Vein and Old Coal; another (7225) for 'Nantyglo (Blaina North)' is dated 1921. (uncertain)

North Gawber Colliery South Yorkshire

• Following the miners' strike of 1984 and 1985 the colliery merged with nearby Woolley colliery; the link was short-lived. David Beilby's account says it closed completely in 1987, where the Durham Mining Museum gives December 1985 — the difference is most likely between the end of coal winding and the end of the site. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Gawber' (catalogue 8094, Barnsley, dated 1925); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

North Tunnel Colliery Merthyr Tydfil

• A pit named simply "Tunnel" is recorded sharing the Lower-Four-Feet, Little/Seven-Feet, Rhas Las/Nine-Feet and Red Vein seams with the wider Dowlais Collieries complex into 1917; very likely the same pit as North Tunnel, though not independently confirmed. (uncertain)

Noyadd Colliery Carmarthenshire

• In 1907-08 it employed 111 men underground and 18 at the surface. (disputed)
• The 1908 list of mines gives 111 underground and 28 surface workers. (disputed)
• NMRS locates the mine at Brynamman, Amman Valley, grid reference 700133; the Cwmgors history says it was presumably somewhere between Garnant and Lower Brynamman but could not find it on old maps. (uncertain)
• Noyadd was a sister mine to Glangarnant; NMRS says it was possibly part of, or the same mine as, Glangarnant. (uncertain)

Nunnery Colliery South Yorkshire

• Wikipedia and Grace's Guide both date the start of mining on the Nunnery site to 1868; the Northern Mine Research Society's account of the 1923 accident says the colliery had been winding coal since 1866. (disputed)
• Forum contributors reported in November 2020 that the capped Nunnery shaft stands inside a conifer-screened enclosure opposite Makro on Parkway Avenue, one of them confirming it from having worked at the depot built over it. (uncertain)

Nutfield and Redhill Fuller's Earth Mines Surrey

• The 'Fulling Earth Field' at Nutfield is first recorded in 1583. (uncertain)

Oakdale Colliery Caerphilly

• NMRS records a workforce of 3,465 in 1928, while the more widely cited peak figure is 2,235 men in 1938 with output around one million tons a year; the two figures are not reconciled by any source consulted. (disputed)

Odin Mine Derbyshire

• Sources disagree on the earliest documentary reference. Wikipedia gives 1280, when a poacher, John of Bellhag, was tried for hunting at Bactor Wood and at the entrance to Odin Mine; the National Trust's own monument record instead gives 1260, describing it as the oldest record of a named mine in Derbyshire. Both agree the mine is the earliest documented in the county. (disputed)
• Much of the old mine is unstable underground: a collapse in 2011 left a hole some 15 m deep in the floor of the main passage, the entrance passages are slippery with black shale mud, and the caving community regards parts of the system as beyond safe reach. (uncertain)

Old Burghclere Lime Quarry Hampshire

• The Derelict Places account states the quarry and kilns were opened in 1885 by Messrs Forders, taken over by British Portland Cement Manufacturers Ltd in 1913, and closed finally in April 1938 for lack of demand. Wikipedia instead says the quarry was actively worked only until the beginning of the 20th century. (disputed)

Onllwyn Colliery Neath Port Talbot

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Onllwyn' (catalogue SW164, Nine Feet, dated 1949); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Parc Mine Conwy

• A 2017 report describes numerous ore chutes and dangerous false floors in the upper levels, with some collapsed sections dropping 70 feet or more, and notes that Level 2 was used for scientific pendulum experiments studying coastal deformation in 1968 before being sealed. (uncertain)
• The mine was formed by amalgamating older workings on the north–south Gors and Fucheslas lodes; the Gors Vein is 12 to 30 feet wide and filled with granular quartz carrying galena and sphalerite, and the ore shoot worked from the Gors Shaft is reputed to have yielded 16,000 tons of lead concentrates alone. (uncertain)

Parkenoweth Mine Cornwall

• Parkenoweth was one of the constituent lodes/workings of the wider Wheal Owles group at Botallack, alongside Wheal Edward, Wheal Grouse, Cargodna, Wheal Boys, Wheal Gendall, Wheal Chase and Lower Boscean. (uncertain)

Parkside Colliery Lancashire

• At least one fatality occurred during the colliery's shaft-sinking phase, before any coal was wound, though no further named detail or date survives in the sources consulted. (uncertain)

Parys Mountain Anglesey

• Copper from Parys Mountain was used to sheathe the hulls of Royal Navy ships, reportedly including vessels of Nelson's fleet. (uncertain)

Peak Alum Works North Yorkshire

• Thomas Chaloner is popularly said to have smuggled Italian papal alum workers out of Italy in casks to found England's first alum works at Guisborough in 1604, earning his own excommunication — a colourful story modern historians regard as apocryphal, though Chaloner did genuinely travel to Italy and did found the works. (disputed)

Penberthy Croft Mine Cornwall

• Sources put the working life differently. The Geological Conservation Review has the mine producing very little by 1840 and believed closed in the late 1840s, but records output again in 1881-83; mine databases give the span as 1798 to 1883, and a 2021 field note says simply that it closed in 1840. (disputed)

Penhalls Mine Cornwall

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Penhalls' (catalogue OMR118C, Tin And Copper Ores, dated 1880); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Pentre Colliery Rhondda Cynon Taf

• Curteis, Greenhill and Ware first opened the colliery in 1857, and by 1864 shafts had been sunk to the steam-coal seams. (uncertain)
• From 1861 the colliery was in the hands of the Pentre and Church Colliery Company, formed by the Cory Brothers; the Inspector of Mines' list for 1896 gives the Pentre Upper and Lower pits as owned by Cory Brothers and Co. Ltd, employing 1,125 men. (uncertain)
• In the twenty years from 1874 production trebled to 159,000 tons a year. (uncertain)
• The colliery employed 1,125 men in 1896, 1,190 in 1908, 795 in 1918 and 838 in 1923. (uncertain)
• A 1923 return gives 838 employed producing from the Upper and Lower Five Feet, Yard and Bute seams. The colliery closed in 1929. (uncertain)
• The explosion of 24 February 1871 is listed among the Welsh mining accidents of five or more fatalities, at Pentre in the Rhondda, with 38 killed. (uncertain)

Penwyllt Quarry Powys

• The Penwyllt Dinas Silica Brick company quarried silica sand at Pwll Byfre and manufactured refractory bricks at the Penwyllt brick works, destined for use in industrial furnaces; a narrow-gauge railway with a rope-worked incline transported silica sand and stones to the brickworks, which stood adjacent to the Neath and Brecon Railway. The works closed in 1937 or 1939. (disputed)
• Three groups of kilns are recorded: two at Penwyllt quarry created in the railway age by Jeffreys, Powell and Williams and dated 1878; a bank of four at Pen-y-foel near the Penwyllt Inn erected around 1863 to 1867, it is thought by the Brecon Coal & Lime Co., with a loading bank for railway wagons in front; and a bank of seven at Twyn-disgwylfa built by Joseph Claypon between 1836 and 1842, largely destroyed by quarry tipping with only one draw arch now visible. (uncertain)

Penyard Colliery Merthyr Tydfil

• One account gives abandonment in 1901; a separate account instead keeps Penyard within the wider Dowlais Collieries group's shared workings (including the Little/Seven-Feet seam, abandoned July 1917) until the whole group's 1924 closure. (disputed)

Pirnie Colliery Fife

• The 1880 official list gives 'Firmey, Methhillhill, Fife Coal Co. Limited' beside the company's Leven pit; this record takes the entry to be Pirnie under a garbled name. (uncertain)

Pitstone Chalk Quarry and Cement Works Buckinghamshire

• The works site is now an industrial estate, with the surviving building converted to offices and listed. (uncertain)

Pochin Colliery Blaenau Gwent

• Welsh Coal Mines says the colliery was named after Henry Davis Pochin, one of the company's directors; the RCAHMW record says it was named after the daughter of that director. (disputed)

Point of Ayr Colliery Flintshire

• An underground explosion in 1899, caused by a flying wedge chipping a safety lamp's glass and igniting methane, killed colliery manager Lewis Jenkins, his deputy Samuel Pearson, and brothers John and Ernest Parry, among others. (uncertain)

Polberro Mine Cornwall

• Over its main working period the mine produced 4,310 tons of tin and 1,598 tons of copper. (uncertain)

Poltesco Serpentine Works Cornwall

• The business wound up in 1893 after the loss of an uninsured cargo at sea, combined with a decline in the fashion for serpentine ornament. (uncertain)
• Most of the works were demolished in the 1930s by a Mr Ironside, after a Council for the Preservation of Rural England survey recommended converting the buildings to holiday accommodation. (uncertain)
• Serpentine slabs from the works were used in Duchy of Cornwall buildings in London, with company showrooms near the Strand; finished goods were shipped through Penryn and Falmouth. (uncertain)

Portland Colliery East Ayrshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Portland' (catalogue S4214, Main, dated 1940); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Potts Ghyll Mine Cumbria

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Potts Ghyll' (catalogue OM15238, Unknown, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Poynton Collieries Cheshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Poynton' (catalogue NW1284, Gees, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Preseli Bluestone Quarries Pembrokeshire

• The quarrying interpretation is disputed: sceptical geologists argue Neolithic people could have collected standing stones from glacial erratics without quarrying bedrock, and that glacial transport rather than human haulage may explain at least some of the bluestones. (disputed)

Prestonhill Quarry Fife

• An estimated two million cubic metres of rock were taken from the site over its working life. (uncertain)

Prospect Lead Mine Derbyshire

• The Alport Mining Company used a nearby building at Broadmeadow as its office while working Prospect Mine, its last mine before closure. (uncertain)

Pulloxhill Gold Mine Bedfordshire

• Accounts of when the mine was abandoned disagree: one has it closed by 1683, another that it was not abandoned until about 1750. (disputed)

Pwllbach Colliery Neath Port Talbot

• The Pwllbach Colliery Co. Ltd, registered on 20 July 1905, survived until 1924, when it went into voluntary liquidation and the mine was taken over by the Pwllbach, Tirbach and Brynamman Anthracite Collieries Ltd. (uncertain)

Quarter Colliery South Lanarkshire

• Buddlepit, drawing on the Northern Mine Research Society, records the colliery as worked from 1873 to 1930. This cannot be the whole story, since the fatal explosion here was in 1841 and Groome describes the village and its ironworks in 1884. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Quarter' (catalogue 5586, Bannockburn Main, dated 1910); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Racecourse Colliery, Hanley Staffordshire

• Accounts differ. Staffordshire Past Track dates the colliery 1840 to 1941 and attributes the closure in May 1941 to the ever-present hazard of flooding and later to dwindling reserves. The Victoria County History states that production ceased at the Racecourse Pits about 1937, after which the Deep Pit was the only colliery still working in Hanley. (disputed)

Ramsley Mine Devon

• A Mining Remediation Authority abandonment plan for Ramsley, seam 'Copper Ore', gives an abandonment date of 9 December 1909 -- earlier than, but broadly consistent with, the wider c.1911-12 closure given by the mine's other sources; the plan most likely records a specific shaft or section abandoned while work continued elsewhere on the site for a further two years. (uncertain)

Redheugh Colliery Tyne and Wear

• Redheugh Colliery was sunk in 1872 and closed on 28 May 1927, the last colliery at work in Gateshead. The 1929 inspector’s report gives the sinking as 1871. (disputed)

Rhigos Colliery Neath Port Talbot

• The colliery page states Rhigos was known locally as 'British Rhonda' and later 'The Pandy', but a detailed addendum on the same page describes British Rhondda as a separate and older complex, itself once called Pandy or Fforchygaran, distinct from Rhigos. (disputed)
• The company was acquired by Harry Llewellyn, described by the source as an Olympic steeplechaser. He was in fact a showjumper, winner of Britain's only gold medal at the 1952 Olympics on Foxhunter, and the second son of the colliery owner Sir David Llewellyn; he also rode in the Grand National, which may account for the description. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Rhigos' (catalogue SWR2008, Nine Feet, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Riddochhill Colliery West Lothian

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Riddochhill' (catalogue S632, Jewel, dated 1956); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Ripley Colliery Derbyshire

• The museum dates the colliery 1846 to October 1949; Wikishire has it worked 1863–1948 and merged with Denby Hall in 1949. (disputed)
• The Mining Remediation Authority catalogue holds abandonment plans titled 'Ripley' (catalogue 4856, Deep Hard and Deep Soft seams, 1905; others for the Blackshale in 1908 and the Ell in 1891 and 1912); none is dated to the colliery's 1949 closure, and the catalogue gives no location, so they may include other Ripley pits. (uncertain)

Risca New Pit Caerphilly

• Welsh Coal Mines records the two shafts as sunk in 1875 by Watts, Ward & Co., with coal first raised in June 1878. Wikipedia instead says a new pit with deeper shafts was sunk by 1872. (uncertain)
• A Western Mail report of 21 December 1892 stated that the Risca collieries were the first in South Wales to be illuminated by electric light both on the surface and at the pit bottom, and that underground traction was by a complete system of compressed-air haulage. (uncertain)
• The 1880 disaster brought the total killed by gas explosions alone at the Risca collieries and the neighbouring Prince of Wales colliery to 591. (uncertain)
• A stay-down strike lasting 72 hours and involving 189 miners took place at the colliery in 1935, in protest at the use of non-union workers. (uncertain)
• The colliery employed 750 men at nationalisation in 1947 and closed in 1967. (uncertain)

River Level Colliery, Aberdare Rhondda Cynon Taf

• Welsh Coal Mines gives 312-314 men employed in 1896; NMRS gives 283 men underground and 31 on the surface (314 total) under manager Rees Howells -- broadly consistent, kept as a single approximate figure. (uncertain)

Robin Hood Colliery West Yorkshire

• An explosion at Messrs Charlesworth's Robin Hood colliery in which a boy was instantly suffocated is reported as 16 February 1836 by one account and 16 February 1838 by another. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Robin Hood' (catalogue 5283, Yard, dated 1908); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Rookhope (Boltsburn Mine) County Durham

• The record's original source says the finest fluorite was sold to German microscope manufacturers such as Zeiss; the British Geological Survey's excursion guide says exceptionally clear crystals were exported to Austria for the manufacture of specialised lenses. (disputed)

Rose Heyworth Colliery Blaenau Gwent

• Coflein and Welsh Coal Mines say the colliery was sunk in 1872 by the South Wales Colliery Company, with first coal raised in 1874. A detailed local history instead has Lawrence Heyworth negotiating for the land in December 1873, advertising in January 1874 for the walls, sidings and yard, advertising between 6 and 14 March 1874 for contractors to sink the new pit, and first coal not until 1876 or 1877. (disputed)
• Coflein and Welsh Coal Mines give the closure as 9 October 1985. A detailed local history gives Friday 20 December 1985, with the colliery officially wound up on 1 January 1986 and about 450 people employed at the end. (disputed)

Rosebush Slate Quarry Pembrokeshire

• An 1889 Ordnance Survey map annotation records that the quarry had provided slate for the roof of the Palace of Westminster, presumably during the post-fire rebuild begun in 1840, though the same source notes the slate was reportedly not of especially good quality for roofing. (uncertain)

Rosedale Ironstone Mines North Yorkshire

• This record dates the east-side workings 1859 to 1929, with a brief reopening from 1919; a 2015 field observation gives the east-side working life as 1860 to 1926. The difference is small and neither source explains it. (uncertain)

Rosemanowes Quarry Cornwall

• Wikipedia dates the trials to 1977–1980 with studies continuing to 1991; Law et al. (2019) describe the Camborne School of Mines programme as running from the late 1970s to the early 1990s, with three deep wells drilled during the first half of the 1980s. (uncertain)

Roslin Colliery Midlothian

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Roslin' (catalogue S660, Browns, dated 1932); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Roundwood Colliery South Yorkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Roundwood' (catalogue 7501, Lindsay (Park), dated 1922); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Sacriston Colliery County Durham

• Wikipedia gives the shaft as sunk in 1838; the Durham Mining Museum gives the colliery as opening in 1839. The Findon Hill Pit was sunk from 9 August 1865. (uncertain)
• By the 1890s the pit employed 600 men and produced 1,000 tons of coal a day. (uncertain)
• On 16 November 1903 water flooded into the 3rd West district of the Busty seam, killing John Whittaker, 25, and Thomas McCormick, 52. When the workings were pumped out, Robert Richardson was found alive on the Friday standing on his coal tub after 92 hours in the dark. (uncertain)
• A fall of stone on 4 December 1940 killed five men — Joseph Welsh, George W. Scott, William Richardson, William Smith and John William Britton — while a party of officials and workmen were removing debris from a previous fall. (uncertain)
• Output was down to 1,500 tons of best-quality coal a week by 1979. The last coal was raised on 15 November 1985 and the colliery closed on 28 December; the Durham Mining Museum gives 15 November as the closing date. (uncertain)

Seaham Colliery County Durham

• The Durham Mining Museum record gives the colliery as closed in 1988, having merged with Vane Tempest on 11 July 1983. (disputed)
• Wikipedia dates the Vane Tempest merger to 1988 and the closure to 1993. (disputed)

Seaton Delaval Colliery Northumberland

• The folk song 'Blackleg Miner' names the village directly — 'Oh, Delaval is a terrible place' — alongside the neighbouring Seghill pit. (uncertain)

Seedlow Lead Mine Derbyshire

• A detailed account of the mine's working between 1764 and 1771 was published by Robert Thornhill in the Peak District Mines Historical Society's own journal in 1962. (uncertain)

Seven Sisters Colliery Neath Port Talbot

• A guide rope broke and tipped men out of the cage, killing Thomas Thomas, 31, his brother John Thomas, 20, and William Lewis, 15. Welsh Coal Mines dates this to 26 August 1979, which cannot be right for a colliery that closed in 1963; 1879 is the likely date. (disputed)
• The first sod was cut on Monday 11 March 1872 by Isabella Bevan, with a silver spade, at Bryn Dulais farm; the colliery and the village took their name from the sisters present. (uncertain)
• The colliery had an elliptical upcast shaft of 12 feet by 9 feet and a downcast of 14 feet in diameter, both sunk to the Nine Feet anthracite seam 200 yards from the surface; the downcast wound coal and the upcast only men. (uncertain)
• The Inspector of Mines' list for 1896 records 296 men; by 1923 there were 607 working the Furnace Four Feet, Brass and Nine Feet Big Vein seams, and at its peak in 1945 the colliery employed over 750. (uncertain)
• Geological problems and changing economic conditions closed the colliery in May 1963; the pit was filled in and the men transferred to the nearby Blaenant Colliery. (uncertain)

Seymour Colliery Derbyshire

• Sinking began in 1855 and the colliery went into production in 1858. The Durham Mining Museum gives the opening as 1873, which the Derbyshire Times report of the 1918 closure contradicts: it describes a pit sunk 'some fifty years ago' with 'a remarkably good working life' behind it. (disputed)

Sharlston Colliery West Yorkshire

• One source records around 1,000 miners employed in 1984; another gives a peak of around 2,200 men working chiefly the Top Haigh Moor seam. Neither source clarifies which period each figure covers. (uncertain)

Sherdley Colliery Merseyside

• Sutton Beauty and Heritage gives the colliery as mining coal from the 1870s until 1944, after which it was retained for pumping, lying near Alexandra and up dip of the company's Lea Green and Bold collieries. The Northern Mine Research Society's own dating of the pit is 1873 to 1943. (disputed)

Sheriff Hill Colliery Tyne and Wear

• The Historic Environment Record gives closure by 1897 and the Durham Mining Museum before 1895, the metal seam having been abandoned in 1892; Wikipedia gives 1926 under the Heworth Coal Company Ltd. (disputed)

Shilbottle Colliery Northumberland

• Accounts differ: the Durham Mining Museum gives 1982, Wikipedia 1981. Both agree the workforce transferred to Whittle. (disputed)

Shireoaks Colliery Nottinghamshire

• The colliery closed in May 1990, a month after joining the South Yorkshire Group; one source instead gives 25 May 1991. (disputed)

Shortwood Colliery South Gloucestershire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Shortwood' (catalogue WM452, Two Feet & Randles, dated 1970); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Shotton Surface Mine Northumberland

• The Wikipedia article dates the permission to 2007; the councillor's report says operations commenced in 2008. (disputed)
• The Wikipedia article says the site employed around 150 people at its height in 2014; the councillor's report of September 2019, during the final phase, gives 117. (disputed)

Shuttle Eye Colliery West Yorkshire

• Engole gives coal got on a small scale from 1837 and the deep colliery begun in the 1850s by Benjamin Lockwood, licensee of the Blacksmiths Arms, with Joshua Ellam, Job Lockwood taking over after 1882 and partnering Benjamin Elliott. (disputed)

Silverdale Colliery Staffordshire

• A mechanisation programme began in 1950 with £20 million invested: a new mine and two drifts from the surface, each of 4,000 yards, to extract 50 million tonnes in the Keele–Hanchurch area, and a new coal preparation plant. (disputed)
• The colliery was completely rebuilt during the 1970s when three new drifts were sunk to exploit new reserves in the Keele area, after which production increased and the pit mined over one million tonnes annually. (disputed)

Silverwood Colliery South Yorkshire

• The Barnsley seam depth is given as 745 yards (heritage group), 740 yards (Shane Phillips collection) and 765 yards (NCB, 1967). (disputed)
• Grace's Guide gives the closure as 1992, citing Wikipedia; the current Wikipedia article and other sources give 1994. (disputed)

Six Bells Colliery Blaenau Gwent

• Winding began in 1897. (disputed)
• Coal extraction is recorded as having commenced in 1898. (disputed)

Skye Marble Quarry Highland

• Closure of the historic quarry is recorded variously as 1914, for the original railway-served quarry, and 1939, for the wider Kilchrist workings; the two figures may refer to different parts of the site and are not reconciled by any source consulted. (disputed)

Slapewath Ironstone Mine North Yorkshire

• Out & About dates the shaft to 1878 under Charlton; Hidden Teesside places the shafts around 1880 and has the mine then operated by Samuelson & Co. Both agree the mine began with Charlton's drift in 1864. (disputed)
• Out & About, following Peter Tuffs's catalogue, has the drift driven under the main road; a descendant of two of the mine's workers states it never did and that only the railway passed under, and the old Ordnance Survey map places the drift south of the road. (disputed)

Slitt Mine County Durham

• One local-history account gives 1878 as the closure date, citing competition from cheaper imported lead and a lifetime output of around 100,000 tons; this conflicts with the primary government output and employment figures showing the mine still working in 1894. (disputed)

Smeaton Colliery Midlothian

• Historic Environment Scotland gives sinking and production as commencing in 1903. The Durham Mining Museum records a death at Smeaton Colliery on 10 January 1877, a quarter of a century earlier: Alexander Bennet, a collier of 21, killed by a fall of coal while shearing head coal. Nothing read here reconciles the two. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Smeaton' (catalogue S2949, Arniston Parrot (North), Splint, Jewel, Cowpits & Great, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Snaefell Mine Isle of Man

• An exploration report from July 2009 found the mine shaft already sealed behind a locked gate, with surface buildings including the former mine captain's house and a chimney still standing. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Snaefell' (catalogue OM5521, Lead Ore, dated 1908); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Snailbeach Mine Shropshire

• Snailbeach is reputed to have yielded the greatest volume of lead per acre of any mine in Europe. (uncertain)

Sneyd Colliery Staffordshire

• The Durham Mining Museum's colliery page gives 55 lives lost in the 1942 explosion, the number killed outright; Wikipedia, Healey Hero and the North Staffordshire Mining Group all give 57, including two men who died later in hospital. (disputed)
• Coal winding at Sneyd ended in July 1962 and the remaining men transferred to Wolstanton, to which the workings had been linked underground; published accounts otherwise give the closure only as 'the 1960s' or 'the 1970s'. (uncertain)

Snowdown Colliery Kent

• The No. 1 shaft was lost during sinking to a sudden water inrush at 260 ft; the Northern Mine Research Society and Dover Museum both record 22 men drowned and the shaft abandoned. (uncertain)
• A detailed local history of the sinking names Edwin Knight as the first man killed at Snowdown, drowned by a sudden inrush of water into the shaft, and does not describe a mass-fatality event. (uncertain)

Snydale Colliery West Yorkshire

• The Featherstone Rovers Archive gives the borehole as 1851; the same author's account at Featherstone's Three Collieries gives 1861. Both agree the shafts were sunk from 1863. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Snydale' (catalogue NE423, Haigh Moor, dated 1948); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

South Crofty Cornwall

• A 2008 report on Robinson's Shaft describes the winding house as roofless and deteriorating despite being otherwise complete, and the bathhouse as retaining period fittings including a lamp rack, 1970s safety posters and showers. (uncertain)

South Leicester Colliery Leicestershire

• The Northern Mine Research Society dates the start of sinking to January 1876; an account of Ellistown village instead says the South Leicestershire Coal Company opened its colliery in 1874, north-east of the crossroads. (disputed)

South Liberty Colliery Bristol

• A Newcomen pumping engine is claimed to have been installed at South Liberty in 1750 and to have remained in use until the colliery closed in 1925; a map of 1769 by Donn does not show a steam engine on the site. (uncertain)

South Terras Mine Cornwall

• It is often stated that Marie Curie herself sourced early radium samples from South Terras; the better-documented historical connection is through Marcel Pochon (a former assistant to her husband Pierre Curie) and the London Radium Institute, and this stronger claim about Marie Curie personally has not been independently confirmed here. (disputed)

Southrigg Colliery West Lothian

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Southrigg' (catalogue 9083, Mill, dated 1924); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Spa Wood Mine North Yorkshire

• Ironstone was extracted between March 1853 and December 1928 on one account, while Buddlepit gives the mine as worked from 1866 to 1930. (disputed)
• East Cleveland's Industrial Heartland gives the Weardale Coal and Iron Company from 1853 to 1890, Sir B. Samuelson and Company from 1890 to 1917 and Dorman Long from 1917 to 1933; Buddlepit gives Tow Law Coal & Iron from 1866, the Weardale companies from 1870, Samuelson from 1889 and Dorman Long from 1923. (disputed)

Speedwell Colliery Bristol

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Speedwell' (catalogue WM283, Mossfield Birches, dated 1878); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Stags Fell Quarries North Yorkshire

• Wikipedia describes the Stags Fell stone as Yoredale Limestone; the National Park and the Lists of Mines describe sandstone, flagstone and slate. (disputed)
• A level track along the fell is probably the course of a 19th-century tramway that took flags to the road for carting to Hawes station. (uncertain)

Stanghow Mine North Yorkshire

• Buddlepit gives the mine as worked from 1872 to 1926; the Wikipedia table of Cleveland ironstone mines gives 1873 to 1925 at NZ654156. (disputed)

Stirling Hill Quarry Aberdeenshire

• A prisoner attempting to escape from the quarry was shot and killed in the 1930s — the only such fatality recorded in the scheme's history — though the sources checked for this record do not give a name or exact date. (uncertain)

Stockdale Colliery North Yorkshire

• The mine reputedly sold its coal at 4d per hundredweight. (uncertain)

Stonecroft and Greyside Mine Northumberland

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Stonecroft And Greyside' (catalogue OM3750, Lead Ore, dated 1897); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Stonehill Colliery Greater Manchester

• The Liverpool Journal of 27 January 1877 names the owners as Messrs Roscow and Ward; later mining-history summaries give the firm as Roscoe and Lord, and record that the colliery was previously known as the Dow Mine. (disputed)
• The colliery was not considered a gassy pit and naked lights were used; the fire is believed to have started when a lad ignited the tarred brattice cloth with his lamp, the flames spreading to the wooden props and then to the coal. (uncertain)

Stotsfield Burn Mine County Durham

• Stotsfield Burn was developed by the Rookhope Valley Mining Company between 1863 and 1884, with access following the customary pattern of a main shaft with an adit level; lead concentrates totalled 1,808 tons from 1863 to 1882 and 104 tons from 1932 to 1940, and fluorspar 15,168 tons from 1905 to 1940. (uncertain)

Strelley Colliery Nottinghamshire

• The scheduling text records the colliery as productive at least into the later seventeenth century. (disputed)
• The account of the wagonway has the Strelley mines worked only until about 1620, by which time all readily recoverable coal had probably been mined, the wagonway being abandoned with them. (disputed)

Sygun Copper Mine Gwynedd

• A 2022 report on mining remains in the hills around Sygun describes waterlogged, dark adits and the surviving structure of an aerial ropeway at nearby Cwm Bychan, noting that the accessible workings show only minor mineralisation and appear to be exploratory trials rather than productive workings. (uncertain)

Taff Merthyr Colliery Merthyr Tydfil

• Production ceased on 30 October 1992 according to one account, though another gives a final shift as late as 11 June 1993; the winding gear was demolished by controlled explosion on 22 July 1994 after a proposed miners' buyout fell through. (disputed)

Talyfan Colliery Swansea

• A Mining Remediation Authority abandonment plan titled 'Talyfan' (SW290, No. 2 Rhondda seam) is dated 1956; no account of the Talyfan workings mentions activity then, so it may belong to another working of the name. (uncertain)

Tan Hill Colliery North Yorkshire

• The colliery was abandoned in July 1935, with three employed that year. (disputed)
• Mining at Tan Hill was abandoned in September 1938. (disputed)
• The last mine closed in 1929, with hand working of the upper seams until the mid-1930s. (disputed)
• Tan Hill miners worked through the 1926 General Strike because their wages were marginal. (uncertain)

Tarbrax Oil Shale Mine South Lanarkshire

• Fatal accidents at Tarbrax over the years are recorded as resulting from falling shale, runaway hutches, explosions and falls from retort platforms, though no single incident is documented in enough detail to stand as its own disaster record. (uncertain)

Team Colliery Tyne and Wear

• The Durham Mining Museum gives the colliery as opened in 1726; the Tyne and Wear Historic Environment Record says the pit is said to have been sunk in 1824. (disputed)
• The Durham Mining Museum and the Wikipedia article on the estate both give the colliery as closing in 1973; the Tyne and Wear Historic Environment Record states that Team Colliery closed in 1941 and the site was subsequently reclaimed. (disputed)
• Antony Gormley's Angel of the North, completed in February 1998, stands on high ground at Eighton Lodge on ground cleared from this colliery. Accounts of Birtley and of the Team Colliery estate say it occupies the site of the pithead baths of the Betty Ann pit; the account of the sculpture itself says the land previously contained a colliery reservoir. The housing estate 322 metres away still carries the colliery's name. (disputed)
• An explosion at the Ravensworth Whin Pit on 10 June 1757 killed sixteen. The only account found is a single sentence in John Sykes's Local Records of 1833. (uncertain)

Teversal Colliery Nottinghamshire

• Teversal was the first colliery sunk by the Stanton Ironworks Company, the shaft begun in the Butcherwood ground; the Durham Mining Museum gives the sinking as started in 1868 and Discover Ashfield gives 1867. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Teversal' (catalogue EM1148, First Waterloo, dated 1980); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Threlkeld Quarry and Mine Cumbria

• A March 2020 permission-visit report describes a steam-powered Ruston Bucyrus excavator surviving in deteriorating condition among the museum's collection, alongside restoration work by Lakeland Mines and Quarries Trust volunteers since 1992 to repair buildings and clear old plant foundations. (uncertain)

Thurcroft Colliery South Yorkshire

• The Rother Vale Colliery Company leased the coal under the Thurcroft estates in 1902 but did not begin sinking a shaft until seven years later. (uncertain)
• Water met within a year of starting, and a fault that had displaced the Barnsley seam and was not discovered until the shaft was sunk, meant no coal was produced until 1913. (uncertain)
• From 1913 the company built housing for the miners, designed by the Rotherham architect James Knight. (uncertain)
• The colliery closed on 6 December 1991. (uncertain)

Ting Tang Mine Cornwall

• The mine's principal shafts were Eldon's, Taylor's and Garland's shafts. (uncertain)
• Ting Tang was one of the important copper-producing concerns in the Gwennap district, with production of approximately 40,000 tons of ore recorded during its operational period; chief produce was copper, alongside pyrites and malachite. (uncertain)
• A Wikimedia Commons specimen description independently records Ting Tang as 'an active mine from 1816-1865' — consistent with, though not identical to, the c.1816-1847 copper production window commonly attributed to H.G. Dines in third-party summaries (that exact figure could not be independently verified this pass; see internal_notes). (uncertain)
• In 1861 Ting Tang was drawn into a large combination with the Consolidated Mines, United Mines, Wheal Clifford and Wheal Squire, known as the Clifford Amalgamated Mines — a name and grouping already recorded on this site's Clifford Amalgamated Mines operator page, whose own account dates the underlying merger of Consolidated Mines and United Mines to 1857. The two accounts are not necessarily contradictory: read together they suggest an initial 1857 merger of the two largest setts, expanded in 1861 to formally bring in Ting Tang and the others. (uncertain)

Tir Edmund Colliery Neath Port Talbot

• NMRS lists the mine under 'Clydach, Swansea Valley', but the Durham Mining Museum, the 1876 notice and the Dyffryn Clydach sources place it among the Dyffryn collieries near Neath. (disputed)
• The Neath poet Elijah Waring wrote a poem about Bryndewi Colliery. (uncertain)
• NMRS gives Bryndewy, Bryn Dewi and Wernddu as other names; a forum contributor citing mine lists reported Bryn Dewi worked by the Neath Abbey Coal Company in 1854 and renamed Tir Edmund under the Main Colliery Company by 1895, with 183 employed. (uncertain)

Tirpentwys Colliery Torfaen

• Tirpentwys Colliery, originally known as Cwmffrwdoer Colliery or Gelli, was the largest in Cwmffrwdoer, working from 1877 to 1969 and including a small level known as Black Vein. (disputed)

Tonfanau Quarry Gwynedd

• The quarry closed in 1998, 106 years after opening, under Hanson, with most of the plant and machinery removed. The same Wikipedia article states elsewhere that a granite quarry existed north of the village only 'until 1992'. (disputed)

Tonge Colliery Greater Manchester

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Tonge' (catalogue NW263, Bent New (Top Neddy) Neddy, dated 1857); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Trefor Granite Quarry Gwynedd

• Coflein and the People's Collection Wales record give the quarry's closure as 1963. (disputed)
• History Points gives the closure as 1971, and Wikipedia's article on the village says large-scale industry ended with closure in 1960. (disputed)

Tregurtha Downs Mine Cornwall

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Tregurtha Downs' (catalogue OMR305, Tin Ore, dated 1891); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Trelewis Drift Mine Merthyr Tydfil

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Trelewis' (catalogue SW106, Mynyddislwyn, dated 1950); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Treskerby Mine Cornwall

• A separate account of the wider Gwennap mining district gives Treskerby's total output as around 32,000 tons of copper ore, notably lower than the sum of the two production figures recorded by Mindat for 1815-32 and 1922-27; the discrepancy is not resolved by either source. (disputed)

Trimdon Grange Colliery County Durham

• A 1905 fatality report records a fall of 144 fathoms (about 263 m) down the shaft, the only located indication of the colliery's shaft depth. (uncertain)

Trimsaran Colliery Carmarthenshire

• J. M. Carey's report on the 1923 accident gives the main slant as 1,350 yards on that date. Welsh Coal Mines, following the contemporary newspaper account, gives 1,400 yards. (disputed)
• Welsh Coal Mines and the Trimsaran Community Council both put the colliery under Amalgamated Anthracite Ltd by 1931, employing about 700 men; the Durham Mining Museum lists the owners as the Trimsaran Colliery Co. Ltd, Welsh Anthracite Collieries Ltd and Henderson's Welsh Anthracite Collieries Ltd before the National Coal Board, without dates. The two are compatible: Amalgamated Anthracite absorbed the Welsh anthracite companies in this period. (uncertain)

Troutbeck Park Green Slate Works Cumbria

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Troutbeck' (catalogue OMR274C, Lead Ore, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Tudhoe Colliery County Durham

• The colliery was also known as Black Horse Colliery. (uncertain)

Tunstead Quarry Derbyshire

• Buxton Lime Firms was formed in 1891 following the amalgamation of 14 lime and limestone companies operating in the Buxton area. (disputed)
• Thirteen firms combined in 1891 to form Buxton Lime Firms Ltd, whose main occupation was to supply chemical-grade lime to Brunner-Mond's Solvay soda plant in Northwich. (disputed)

Tylorstown Colliery Rhondda Cynon Taf

• Durham Mining Museum and Welsh Coal Mines date the explosion 28 January 1896; NMRS, Heneb and the 2005 memorial give Monday 27 January 1896. (disputed)
• NMRS gives No.8 bought and deepened by David Davis and Sons in 1892 and Nos. 6 and 7 bought in 1894; Heneb gives Penrhys (Nos. 6 and 7) bought in 1894 and Pontygwaith (No.8) in 1896. (disputed)
• Welsh Coal Mines and NMRS date No.9 Pit to 1907; Heneb says an additional pit was sunk in 1901. (disputed)
• On 8 April 1913 a fall of stone in No.8 Pit buried five men; James and Lewis Davies, Llewellyn Thomas and John Evans died and Thomas Ashton survived. Welsh Coal Mines gives the fall as about 500 tons and the rescue as about 11 hours; NMRS gives 150 tons. (disputed)

Tymawr Colliery Rhondda Cynon Taf

• Welsh Coal Mines dates the merger to 1958; this archive's own Lewis Merthyr record dates it to 1960. (disputed)
• Welsh Coal Mines gives June 1983; this archive's own Lewis Merthyr record gives July 1983. (disputed)

Tynedale Colliery Northumberland

• Tynedale Colliery had no rail connection and relied on road transport. (disputed)
• The Acomb Coal Co.'s 1919 registration notes describe its collieries as connected with the L. & N.E. Railway. (disputed)

Tynemount Colliery East Lothian

• Historic Environment Scotland records sinking and production as commencing in 1924. The Fourth Statistical Account of East Lothian says the colliery was sunk in 1925. (disputed)
• Historic Environment Scotland gives the colliery as closed in 1952 and abandoned in 1962. The Fourth Statistical Account gives the closure as 1962, which is the abandonment date rather than the end of working. (disputed)

Tynewydd Colliery, Porth Rhondda Cynon Taf

• Welsh Coal Mines records two shafts, each 90 yards deep, sunk in 1852 to the No. 2 and No. 3 Rhondda seams. (disputed)
• The manager told the 1877 inquest the pit was about 17 feet by 12 and about 88 yards deep to the No. 3 Rhondda. (disputed)
• A newspaper of 12 April 1877 put the workforce at about 100 men; the manager told the inquest 150 men and 15 horses, raising about 160 tons a day. (uncertain)

Tynybedw Colliery Rhondda Cynon Taf

• The Durham Mining Museum gives the closure as January 1935; Welsh Coal Mines gives 1933. (disputed)

Tynywain Colliery Neath Port Talbot

• A level called Tyn-y-Wain at Clydach was abandoned in January 1946; the source treats this as possibly, but not certainly, the same site as Tynywain Colliery. (uncertain)

Tywarnhayle Mine Cornwall

• The Cornwall and Scilly Historic Environment Record describes surviving remains of a 1906 flotation plant -- concrete walls, loadings, a tank and a chimney -- which it calls the remains of 'the world's first commercial froth flotation plant'; no other source corroborates this specific superlative, though multiple sources agree an early Elmore flotation trial took place here in 1906. (disputed)

Ubberley Colliery Staffordshire

• The museum gives 1855 to 1900; the pit was paying church rates in 1836 and the abandonment catalogue has all seams abandoned prior to 7 September 1904. (disputed)
• C. J. Homer installed a vertical winding engine before 1875 and the refurbished pit became known as New Ubberley. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Ubberley' (catalogue 13538, Banbury Cockshead Sparrow Butts, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Udston Colliery South Lanarkshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Udston' (catalogue 6814, Humph, dated 1934); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Underwood Colliery Nottinghamshire

• Three dates are given and no source reconciles them. Healey Hero has Barber Walker taking the Selston or Underwood working over in 1728, when it was probably outcrop or opencast, and sinking a vertical shaft in 1831. The Durham Mining Museum gives the colliery as opened in 1855. Mining Heritage puts the sinking of Selston, in brackets Underwood, at 1875, among the new pits of the 1860s and 1870s. The 1842 Children's Employment Commission covered a 140-yard shaft here, which rules out both 1855 and 1875 as the start of working on this ground. (disputed)

Unity Brook Colliery Greater Manchester

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Unity Brook' (catalogue 1261, Doe, Five Quarter, Trencherbone, Cannel, dated 1881); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Upton Colliery West Yorkshire

• Work started on the site in 1924 and two shafts were sunk through 1925 and 1926 to between 260 and 300 yards, but preliminary works meant no coal was raised until 1927. (uncertain)
• The colliery was run by the Upton Colliery Company (Bolckow, Vaughan and the Cortonwood Company) from 1924 to 1939, by Dorman Long from 1939 to 1947, and by the National Coal Board from 1947 to 1964. (uncertain)
• The National Coal Board opened new pit-head baths costing £115,000 in 1952 and spent a further £500,000 in an effort to raise saleable output from 24 to 27 hundredweight a shift. (uncertain)
• An explosion in the Barnsley seam on 20 May 1964 led to the colliery being evacuated and the area sealed, rendering the mine unworkable; with bad geology in the seams the site closed in November 1964. (uncertain)

Usworth Colliery Tyne and Wear

• An outburst of gas ignited by a naked light on 5 June 1850 killed thirteen. (uncertain)

Varteg Hill Colliery Torfaen

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Varteg' (catalogue SWR670, Red, dated 1964); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Vauxhall Colliery Wrexham

• The two sources agree on 1896 — 361 underground and 64 on the surface, 425 in all — but not on 1923: Welsh Coal Mines gives 535 underground and 111 on the surface, 646 in all, against the Durham Mining Museum's 578. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Vauxhall' (catalogue 10608, Top Yard (Smith'S), Seven Feet (Two Yard) ,Quaker (Brassey), Main, Brassey (Crown), Upper Yard (Probably Stone) ,Middle Stone, Lower Yard (Ruabon Yard), Wall And Bench, dated 1931); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Ventonwyn Mine Cornwall

• Cornish Mine Images gives 138 tons of tin from the 1903-1907 working. (uncertain)
• A 2026 account gives 167 tons of black tin between 1889 and 1909, after which the mine was abandoned, and a shaft about 350 feet deep. (uncertain)

Wallsend Colliery Tyne and Wear

• Co-Curate gives the colliery as active between 1778 and 1935; the Durham Mining Museum records it as opened before 1782 and leaves the closure date blank. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Wallsend' (catalogue 3021, Tupton, dated 1893); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Wanlockhead Dumfries and Galloway

• Lead mining at Wanlockhead is generally described as having ceased altogether by the end of the 1930s; at least one source instead states mining finished in the 1950s. (disputed)
• Gold from Wanlockhead, reportedly up to 22.8 carats pure, was said to have been used in making the Scottish Crown. (uncertain)

Waterfall Mine North Yorkshire

• Buddlepit gives the mine as worked from 1892 to 1901 under the Cargo Fleet Iron Co. Ltd; the Wikipedia table of Cleveland mines gives Waterfall at Guisborough, 1880 to 1901, at NZ626172. (disputed)

Waterland Colliery South Lanarkshire

• A 1915 newspaper report on a new colliery shaft being sunk nearby recalls an older 'Waterlands Pit' on the opposite side of the road, worked some forty years earlier (around 1875) and owned by Loudon and Miller -- the same partnership behind the neighbouring East Law Colliery. (uncertain)
• Thomas Hamilton, a brick and tile manufacturer based at Park House, Carstairs, is documented working a brickfield at 'Waterlands by Carluke' from at least 1861, alongside other works at Auchengray, Pool, Carmichael and Braidwood -- the same Hamilton family name the 1880 return gives for the colliery, though the two businesses are not confirmed as the same concern. (uncertain)

Wearmouth Colliery Tyne and Wear

• At least 300 men are recorded to have died at Wearmouth Colliery over its 158-year working life. (uncertain)
• Three boys were killed in a shaft fall at Wearmouth in 1837. (uncertain)

Wednesbury Oak Colliery West Midlands

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Wednesbury Oak' (catalogue 17274, Thick Coal, dated 1877); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Weetslade Colliery Tyne and Wear

• The Tyne and Wear HER entry states that mining ceased in 1960, with washing and sorting of Burradon coal continuing to 1980; the DMM, Co-Curate and the 1964 and 1965 seam returns all indicate coal was worked until 1966. (disputed)

Weigfach Colliery Swansea

• An explosion on 9 March 1877 killed eighteen according to the colliery page, which names eighteen men and boys; the site's list of Welsh mining disasters gives 19. (disputed)
• The Old Weigfach colliery was sunk in the early 1840s, purchased by Thomas Stick in 1844 and sold to Ebenezer Davies in 1849; an advertisement in the Cambrian of June 1856 offered the plant of Weigfach and Cwmbach collieries for sale. (uncertain)
• Thomas Glasbrook developed the New Weigfach colliery, which struck the rich bituminous seam in 1870. It was also known as New Worcester and was worked in conjunction with the Worcester pit. (uncertain)
• From 1874 the colliery began supplying coal to the Landore Steel Company. (uncertain)

Weldon Stone Quarries Northamptonshire

• The only local building material employed extensively beyond the region was the Weldon Stone of the Upper Lincolnshire Limestone, said to have been used in the old St Paul’s Cathedral which was destroyed by fire. (uncertain)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Weldon' (catalogue OM15255, Gypsum, dated 1969); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Wellesley Colliery Fife

• Sources differ on the workforce: Canmore records an average of 1,908 with a peak of 2,603 in 1957, while the Northern Mine Research Society gives an average across the pit's life of 1,208 underground and 342 on the surface. (disputed)
• Methil Docks were fed directly from the colliery and its coal-washing plant at Denbeath; after the 1907 enlargement the works employed over 1,600 people and handled more than 3,500 tons a day. (uncertain)

Wellington Pit Cumbria

• An explosion on 11 May 1910 in the No. 3 North District killed 136 men and boys — the figure given by the official adjourned inquest. (disputed)
• The death toll is given elsewhere as 147. (disputed)

Werfa Colliery Rhondda Cynon Taf

• The Old Pit was sunk to just below the Five Feet seam at 509 feet (BGS figures, with a caution that reports vary). (disputed)
• The shaft was sunk about 66 yards to the bottom of the sump. (disputed)
• The chain breaking in the balance pit on 4 September 1851 killed eleven by one count and fourteen by another on Welsh Coal Mines, and sixteen by NMRS. (disputed)
• The lease ran out on 25 March 1909 and the mine was abandoned. (disputed)
• The colliery closed in 1908 with 257 men. (disputed)

West Cannock Colliery Staffordshire

• A 17 May 1933 House of Commons statement on the previous day's explosion at West Cannock No. 5 gave three men killed and three seriously injured; other records of the same disaster give six dead -- both figures are recorded rather than silently reconciled. (disputed)

Westminster Colliery Wrexham

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Westminster' (catalogue NW1398, Brassey, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Westthorpe Colliery Derbyshire

• The Derbyshire Times of 5 February 1927 reported that J. and G. Wells built six hundred houses at Killamarsh for its workers. Whether all six hundred were built is uncertain: a recession in colliery and council housebuilding followed the next year. (uncertain)

Wharncliffe Wood Ganister Mines South Yorkshire

• A gravity tramline carried crushed ganister down from the mines to the Great Central main line, opened in 1845, for transport to the fire-brick works. (uncertain)
• Total ganister output from the valley was recorded at around 40,000 tons in 1908. (uncertain)
• The mines were driven as roughly horizontal passages of horse-shoe section, linked by stone-lined tramways contouring the hillside to a gravity incline down to the railway. (uncertain)
• Recording work between 2017 and 2023 found most entrances along the tramway sealed or blasted shut and the lower workings seasonally flooded. (uncertain)
• Steetley took over the Oughtibridge works in 1947; by the 1980s Sheffield Refractories Ltd held the northern part of the site, the southern half having been given over to housing. (uncertain)

Wheal Busy Cornwall

• Sources differ on the date and the machine. Grace's Guide has a Boulton and Watt pumping engine installed late in 1777, the first of its type in Cornwall; other accounts describe Watt rebuilding Smeaton's 72-inch engine of 1775 in 1778. Both agree Wheal Busy was where Watt's engine first worked in the county. (disputed)
• Figures differ by phase and are not directly comparable: 27,000 tons of arsenic is given for the mine's life, against 750 tons raised between the 1907 plant opening and closure. No source consulted reconciles the two. (disputed)

Wheal Damsel Cornwall

• Widely repeated figures give Wheal Damsel's working life as 1815-1872 with around 37,000 tons of copper ore produced, and West Wheal Damsel (Wheal Spinster) as worked 1852-1874 for a further 29,150 tons -- both traced to Mindat, which could not be independently read for this pass. (uncertain)

Wheal Fortune Cornwall

• Documentary evidence suggests mining activity on the site may date to 1508, recorded under early names "Cog-an-bans" or "Goghan Bras"; tin veins from this period, called the Conqueror branches, are still traceable — a 2007 caving-forum discussion of the site independently refers to old, probably 18th-century, exploratory levels at 'The Conqueror' branch. (uncertain)
• The mine continued under different companies until 1912, briefly renamed New Great Wheal Fortune in 1908-09; a lone miner is reported to have worked its burrows for wolfram in the 1950s, recovering about two sacks a day. This later-phase detail is sourced to Wikipedia alone and not independently corroborated in this pass. (uncertain)

Wheal Harmony Cornwall

• A Mining Remediation Authority abandonment plan for the combined workings, titled 'Treleigh Consols New Wheal Harmony Wheal Maria', carries an abandonment date of 1864 — a data point suggesting some further activity or amalgamation during the period most secondary accounts describe simply as dormant between the 1844 closure and the 1872 reopening, though the plan's own record gives no further operational detail. (uncertain)

Wheal Jane Cornwall

• A January 2007 report describes an emergency light still on and a transformer still humming in the main processing building at Wheal Jane several years after closure, alongside catwalks, control panels and floors under one to three inches of red mine water. (uncertain)

Wheal Owles Cornwall

• One account gives the mine's deepest workings as around 190 fathoms. (disputed)
• Another account gives a maximum depth of over 200 fathoms (about 1,200 feet). (disputed)
• The mine never reopened after the 1893 flooding despite a later attempt to float it as 'Wheal Owles and Boscean United'; ownership of the sett later passed to Geevor Tin Mines plc, though no further extraction is recorded there. (uncertain)

Whitburn Colliery Tyne and Wear

• The Durham Mining Museum gives the closing date as 31 May 1968; other accounts record the final shift coming up from the shaft bottom on 8 June 1968. (disputed)

Whitby Jet Workings North Yorkshire

• Slight accidents were reported as frequent among jet miners; in 1873 a miner was reported killed by a fall of shale. (uncertain)

Whitecliff Ironworks Gloucestershire

• The ironworks was built between 1798 and 1801 by a partnership including Teague (named James by one source, Moses by another), Samuel Botham and John Bishton, later joined by William Phillips; flooding (dated to winter 1797-98 by one source, 1799 by the other) destroyed the partly-completed works and forced Botham to withdraw. (disputed)
• David Mushet was brought in by Thomas Halford (in 1810 per the Forest of Dean Local History Society, 1809 per Grace's Guide) to manage the works and take a partnership share, conducting some of his earliest steelmaking experiments there before withdrawing after a few months. (disputed)

Whiteside Mine North Yorkshire

• The history of lead mining in Swaledale is believed to go as far back as the 2nd century BC, though the first written records of lead being worked in the Grinton area are documents dated 1219. (uncertain)

Whitwood Colliery West Yorkshire

• The Pitwork account makes the Silkstone shaft 415 yards deep. The company's own history describes the Silkstone pit as sunk for a prospective output of 1,000 to 2,000 tons a day from 440 yards, a figure likely to be the working depth rather than the shaft. (disputed)
• The Durham Mining Museum's Pitwork account gives the two shafts as sunk between 1871 and 1878. Altofts Cricket Club's history of the pit gives the sinking as 1874 with coal reached on 14 December 1876, which falls inside that span rather than contradicting it. (uncertain)

Whitworth Colliery Neath Port Talbot

• A Welsh Coal Mines forum contributor, citing the companies' own registration and dissolution dates, records that Whitworth Collieries Ltd was registered 12 February 1905, passed into German-controlled directorship in October 1906, cut its first sod 29 April 1907, and suspended sinking in November 1911 owing to the death of a Mr de Frietas — an additional or alternative cause to the water and cost problems NMRS records. (disputed)

William Gill Colliery North Yorkshire

• A visitor in about 2010 judged the covered shaft to be at least 100 feet deep. (uncertain)

Williamthorpe Colliery Derbyshire

• The Durham Mining Museum gives the sinking as started in 1905, which is the year the shaft was completed rather than begun. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Williamthorpe' (catalogue EMST8, Spoil Tips, dated 1979); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Willington Colliery County Durham

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Willington' (catalogue D983, Hutton 'L', dated 1915); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Wimblebury Colliery Staffordshire

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Wimblebury' (catalogue WM191, Bass, dated 1957); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Windlestone Colliery County Durham

• Whellan's Directory of County Durham for 1894 says the Windlestone pit was laid in 1874 and that the village had become almost deserted because Pease and Partners closed the pit that year. This cannot be reconciled with a shaft completed in 1877 or with the employment figures showing 66 men in 1883, and one of the two accounts must be wrong. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Windlestone' (catalogue 10655, Various, dated 1931); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Winster Mines Derbyshire

• Lead mining in the Winster area is thought to date back to Roman activity in this part of Derbyshire. (uncertain)

Wolfcleugh Mine County Durham

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Wolfcleugh' (catalogue OM15150, Fluorspar Lead Ore, dated 1955); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Wollaton Colliery Nottinghamshire

• Wollaton Colliery discharged water from its bathhouse into the Nottingham Canal until its closure in late 1963. (disputed)
• healeyhero's register of deaths at the pit covers 1873 to 1966, implying working into the mid-1960s. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Wollaton' (catalogue EM1265OC, Coombe, dated 1985); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Wood Level Colliery Pembrokeshire

• Wood Level is repeatedly described in secondary accounts of the Pembrokeshire Coalfield as the last colliery working anywhere in the county, closing in 1950 -- a mundane, consistently repeated fact, though no primary listing or plan naming Wood Level itself by that name has yet been directly read. (uncertain)

Woodhorn Colliery Northumberland

• Around two thousand people worked at Woodhorn, in a hierarchy of hewers, putters and trappers. (uncertain)

Woolley Colliery South Yorkshire

• A £40 million NCB investment including a West Side coal preparation plant was announced in 1982, and a fire destroyed part of it in 1983, causing £8 million of damage. (uncertain)

Workington Colliery Cumbria

• An explosion of firedamp at the Isabella Pit on 21 September 1833 killed thirteen, among them three Brennan brothers, the youngest aged fourteen. (uncertain)
• The colliery worked through the Buddle, Isabella and Jane pits, with the Union and Lady pits also named among those lost in 1837. (uncertain)
• The colliery belonged to Mr Curwen at the time of the 1837 inundation and is recorded under Irving & Co. in the 1860s. (uncertain)

Wyken Colliery West Midlands

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Wyken' (catalogue EM1127, Rider (Two Yard & Ryder), dated 1880); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Ynysfeio Colliery Rhondda Cynon Taf

• The museum records closure in April 1930; Welsh Coal Mines says production ceased during the 1930s and the colliery was kept as a pumping station in 1945. (disputed)
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Ynysfeio' (catalogue SWR1364, Four Feet, dated 1916); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Ynyshir Colliery Rhondda Cynon Taf

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Ynyshir' (catalogue SWR2403, No 2 Rhondda, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain)

Disasters

Abercynon Colliery Haulage Accident, 1906

• The mechanism of the runaway is not established by the sources read here. The Northern Mine Research Society's account attributes it to the breaking of the big link of the chain attaching the haulage rope to the journey, but that page could not be retrieved and has not been read. (uncertain)

Abercynon Colliery Sinking Accident, 1893

• David Jones, aged 46, died on 22 February 1893 of injuries received in the same fall; the sources nonetheless give the accident's toll as eight. (uncertain)

Alps Quarry Fall of Stone, 1889

• The three men killed were Charles Harding, George Richards and James Wills; Harding was brought out of the fall alive but died about an hour later of a fractured skull and complications, shortly before arriving at hospital. (disputed)
• The inquest at Cardiff was held on the bodies of George Richardson, Charles Cavill and James Wills, killed by a fall of stone at Alps Quarry. (disputed)

Annesley Colliery fire and afterdamp

• Seven men died: William Waplington, Thomas Ward, Samuel Abbott, Joseph Pickard, Thomas Webster, George Rye and Bradbury. The Durham Mining Museum record dates the deaths to 27 June 1877 and the inquest transcriptions agree; accounts drawn from the Inspector’s report place the incident on 26 June. (disputed)
• The two surviving lists of the dead disagree on their ages. The memorial record gives Waplington 37, Bradbury 16, Ward 55, Abbott 19, Webster 45, Pickard 45 and Rye 26; the Nottinghamshire inquest transcriptions give Ward 36, Abbott 24, Pickard 29, Webster 50, Rye 27 and Bradbury 17, and name the last as Joseph rather than James. (disputed)
• The Inspector of Mines reported that six lives were lost, but seven men are listed in the appendix to the same report, and seven are named on the memorial. (disputed)

Auldhouseburn Colliery inundation, 1898

• Three men drowned: John Hazel, William Gemmell and James Shaw. The Durham Mining Museum's list, taken from the Inspector's report, gives the names as John Hazel, aged 33, William Gennell, aged 47, and James Straw, aged 20, so the surnames of two of the three are spelt differently in the official list and the newspaper reports. (disputed)
• The Scotsman gives James Shaw as seventeen and the mainstay of a widowed mother; the Durham Mining Museum's list gives his age as twenty. (disputed)
• Nineteen men were cut off in the rise workings; sixteen were brought out alive after roughly twenty-four hours underground, and the newspaper compilation describes them as entombed for twelve hours. (disputed)

Barrow Colliery shaft accident, 1874

• Welsh Coal Mines names the fifth victim as John Lewis (36); NMRS names him as J. Rook (23), a sinker. The other four names and the cause agree between the two accounts. (disputed)

Bartonholm Colliery explosion, 1871

• The Scotsman of 1 November 1871 reported four men killed by the explosion — William Graham, Charles McDonald, Thomas McQuade and Samuel Holmes — while the Hamilton Advertiser of 4 November reported five, adding William Gilmour, with three others so seriously injured that their recovery was doubtful. (disputed)
• The Durham Mining Museum dates the deaths to 30 October 1871, and both newspaper reports place the explosion at about three o'clock on the Monday morning, which was 30 October. (disputed)
• The Scottish Mining Website heads its account 31 October 1871. (disputed)
• The Durham Mining Museum gives different ages, Graham 38, Holmes 36, McDonald 40 and McQuade 35, and records the first three as brushers and McQuade as fireman. (disputed)

Bedwas Navigation Colliery Explosion, 1912

• Welsh Coal Mines records twelve men badly injured, three of whom later died; Wikipedia gives three killed and nine seriously injured. (disputed)

Bedwellty Pits Explosion, 1865

• The Welsh Coal Mines death roll and the Museum Wales record of the Illustrated London News prints both give 16 June 1865; the Welsh Coal Mines list of disasters gives 21 June. 16 June is followed. (disputed)
• The explosion at the No. 1 pit killed twenty-seven miners, six of them boys under the age of sixteen. (uncertain)

Bersham Colliery explosion

• Nine men died. The Northern Mine Research Society names them as William Pattison, 57, manager; Joseph Mathias, 34, fireman; Edward Owen, 49, fireman; John Johns, 42, fireman; James Roberts, 36, fireman; Henry Valentine, 44, pitman; Thomas Evans, 32, collier; Edward Parry, 36, collier; and Robert Lloyd, 39, hooker-on. Welsh Coal Mines gives several of the ages differently — Pattison 56, Mathias 36, Owen 45, Evans 23 — and the fireman the society calls John Johns it calls John Jones. (disputed)

Birley Vale Colliery Explosion, 1876

• The press roll gives Ellis Cooper, James Woodward, Thomas Marples senior, Thomas Marples junior, Edward Saville and Joseph Kelley; the inspector's report names three of the bodies taken into Yorkshire as Ellis Cooper, Thomas Marples and George Kelly. (disputed)

Black Vein Colliery explosion, 1846

• The dayshift fireman was sick and his brother was sent to check the mine; he was said to be beating out the gas with his coat when it exploded. (uncertain)

Black Vein Colliery explosion, 1860

• Welsh Coal Mines gives 146 men and boys killed on 1 December 1860; Wikipedia says more than 140, and other accounts give 142. The exact figure is not settled. (disputed)
• A chronology compiled on the Welsh Coal Mines page gives 142 killed. (disputed)

Blackrod Colliery explosion, 1836

• Official records gave eleven lives lost, but local press reports of inquests held under three coroners, at Adlington, New Springs and the Cock Inn at Blackrod, listed twelve; the Durham Mining Museum names the same twelve. (disputed)
• The fireman Thomas Challender is 38 in the CMHRC account and 36 on the Durham Mining Museum page. (disputed)

Blaenclydach Colliery spake runaway, 1941

• The Welsh Coal Mines colliery page gives twenty-five injured. (disputed)
• The Welsh Coal Mines 1941 fatality list gives 27 seriously injured and 26 with minor injuries. (disputed)

Blaengwawr Colliery Explosion, 1861

• The Welsh Coal Mines colliery page dates the explosion 6 March 1861, against its own death roll and the contemporary newspapers. (disputed)

Blaenhirwaun Colliery explosion, 1955

• Four men were killed in the explosion and two of the injured died later in September, making six. (disputed)
• The Welsh Coal Mines colliery page gives five: four killed and David Pennington, who died some weeks later. (disputed)

Boosbeck subsidence, 1883

• East Cleveland's Industrial Heartland dates the mine's closure to 1887 (water continuing to fill the workings after a 1886 feeder was struck); Durham Mining Museum's own colliery record gives 1886. (disputed)

Bothwell Castle Colliery shaft accident, 1889

• NMRS dates the accident to 28 June 1889; the Durham Mining Museum's colliery summary instead gives 28 June 1899, though its own named-victims list does not overlap with NMRS's five names. (disputed)

Britannia Colliery compressed-air main explosion, 1938

• The NMRS gives the younger victim as Roland Bertram Bond, 23, of William Street, Tir-y-berth. (disputed)
• Welsh Coal Mines lists him as Roland John Bond, 23, welder. (disputed)

Broadoak Colliery explosion, 1897

• Welsh Coal Mines gives Morgan Sanders's age as 23; NMRS gives 32. The other four names and ages, and the cause, agree between the two accounts. (disputed)

Brookhouse Colliery Overwind, 1958

• The official Ministry of Power inspector's report records no fatalities. A family member's testimony submitted to HealeyHero states that Derrick Smith ('Carrots') was killed in the incident, leaving a pregnant wife and two young sons. This claim has not been corroborated by any official record found, and is recorded here as a disputed family account rather than an established fact. (disputed)

Brynamman Colliery Inrush, 1933

• The water broke into the Brass Vein Slant. (disputed)
• The inrush was in the Trigloyn Slant, Brynamman Colliery. (disputed)

Bryncoch Colliery inundation, 1859

• Welsh Coal Mines names Fox, Redwood and Co., who had drained and reopened the pit in 1854, as the owners; the account on Healey Hero gives the Neath Abbey Coal Company. (disputed)
• Welsh Coal Mines says the water had risen 80 feet up the shaft by late afternoon; the account on Healey Hero says 7 feet at 11 a.m. and 96 feet by 4 p.m. (disputed)
• The overman ran round the pit to get the men out but was washed away when the water reached the roof; the Inspector, Mr Evans, praised his courage in sacrificing his life for his men. He is John Dorman on Healey Hero's first list and Robert Dorman, 45, in the Cambrian's list and on Welsh Coal Mines. (disputed)

Bryndu Colliery explosion, 1852

• Welsh Coal Mines dates the explosion Thursday morning, 11 November 1852, on its colliery page and fatality list. (disputed)
• The NMRS dates it 18 November 1852. (disputed)

Bryndu Colliery explosion, 1853

• William Johns is 27 on the Welsh Coal Mines colliery page and in the NMRS account, and 37 in Welsh Coal Mines' 1853 list. (disputed)

Bryndu Colliery explosion, 1858

• Welsh Coal Mines dates the explosion 28 May 1858 and names twelve dead. (disputed)
• The NMRS dates it about 5 p.m. on 27 May 1858 and gives eleven killed, again by a naked light. (disputed)

Bryngwiog Lead Mine Inundation, 1862

• Sixteen men perished when water from old workings flooded the mine. (uncertain)
• Water from old workings broke into the mine. (uncertain)
• The dead were named as Edward Jones of Moel-y-Crio, Bennet Roberts of Lixwm, William Pierce of Rhewl, Edward Jones of Rhesycae, John Jones of Foel, Richard Blackwell of Llaneurgain, William Hooson of Cilcen, Job Jones and others — villages spread right across Halkyn Mountain. (uncertain)
• The villages around the mine have a lead-mining history going back centuries, several buildings in the Wern-y-Gaer area of Rhosesmor being more than three hundred years old. (uncertain)

Bryngwiog Mine inrush, 1862

• The Northern Mine Research Society dates the inrush to 12 February 1862; welshcoalmines.co.uk's death roll instead gives Saturday 22 February 1862. (disputed)

Brynlliw Colliery roof fall, 1963

• Hansard for Monday 13 May 1963 refers to the accident at Brynlliw on Friday 10 May, and the Welsh Coal Mines 1963 fatality list dates the deaths to the 10th. (disputed)
• The Welsh Coal Mines colliery page gives 17 May 1963. (disputed)

Bunker's Hill Colliery Explosion, 1875

• The inspector's report, Healey Hero and the Northern Mine Research Society index all give forty-three killed; the North Staffordshire gazetteer gives forty-two. (disputed)

Bwllfa Colliery Fire (1867)

• A second source (welshcoalmines.co.uk) names the five victims slightly differently -- Benjamin Lloyd (46), Thomas Wood (35), Benjamin Thomas (57), Thomas Owen (24) and John Daniel (50) -- against the NMRS record's Richard Lloyd (44), Thomas Wood (28), Thomas Howell (28), Benjamin Thomas (55) and John Daniel (50); both are kept on record rather than silently reconciled. (disputed)
• The exact ignition source was never conclusively established, though friction from a wire rope being lowered past the burning air tube was suspected. (uncertain)

Cadean Slant manrider accident

• Ten men were killed. The Northern Mine Research Society's account of J. M. Carey's report and Welsh Coal Mines both give ten and name the same men; the Durham Mining Museum also gives ten. The Daily Mail of 27 April 1923 reported nine, seven killed outright and two who died on the way to hospital, a count taken before every death was known. (disputed)
• Carey's report gives the main slant as 1,350 yards on the date of the accident. Welsh Coal Mines, following the contemporary newspaper account, gives 1,400 yards. (disputed)

Caedean Slant explosion, 1909

• Welsh Coal Mines gives Owen Thomas's age as 30; at the opening of the inquest the witness identifying him gave it as 38. (disputed)

Caprington Colliery Inrush

• The jury's verdict records the deaths as occurring on the 9th or 10th of December 1909, while the inspector's report dates the inrush firmly to 11.45 p.m. on the 10th. (uncertain)

Cardowan Colliery explosion, 1982

• 25 casualties (7 stretcher cases) per the same-day Commons statement. (disputed)
• 40 casualties in total (36 burns, 18 of them over 15% TBSA; 6 mechanical injuries, 1 life-threatening; 19 with mild respiratory upset) per the clinicians' published account, the fuller and later-established figure. (disputed)

Celynen Colliery roof fall (1909)

• Joseph Absalom's age at death is given as 35 by Welsh Coal Mines' compiled fatality record and as 36 by the Durham Mining Museum. (disputed)

Chartershaugh Colliery Explosion, 1778

• 24 men were killed per contemporary and secondary accounts; Durham Mining Museum's own burial records confirm 17 individuals by name and note the collection is incomplete. (disputed)

Chatterley Whitfield (Whitfield) Colliery explosion

• The Northern Mine Research Society's account gives 26 men killed underground, rising to at least 28 once deaths from injuries at the surface are included. (disputed)
• Other secondary accounts give the toll as 21 or 24 men and boys. (disputed)
• The Durham Mining Museum names twenty-four men and boys killed on 7 February 1881, and the colliery's own published history gives twenty-four. Contemporary accounts give twenty-one killed with about six bodies unrecovered, and totals as high as twenty-eight have been published. (disputed)

Clifton Hall Colliery explosion

• Morley's official report tabulates 177 deaths and lists 177 names, and the plan of the mine showing where the bodies were found marks only 157 positions. (disputed)
• The title of the minutes of proceedings in the same official report says 178 men and boys were killed; the memorial at St Augustine's records 178, and the Durham Mining Museum and modern accounts follow that figure. (disputed)

Cribbwr Fawr Colliery electrocution, 1909

• Welsh Coal Mines names the younger man Owen Davies, 24, a single man; the Durham Mining Museum, from the Inspector's report, names him Owen David, 28. (disputed)

Cwmbran Colliery scalding, 1866

• Welsh Coal Mines gives John Morgan as the stoker and Robert Allen as the haulier; the Durham Mining Museum gives Allen as the stoker and Morgan as the haulier, recording all three deaths as 'boiler explosion'. (disputed)

Cwmnantddu Colliery Explosion, 1849

• Five were killed: William Cooke, William Jeffries, Samuel Ball, and James Crumbs with his son William, aged about fourteen. (uncertain)
• The New Pit at Cwmnantddu was at this date the property of the Pentwyn and Golynos Company. (uncertain)

Cwmtillery Colliery Explosion, 1876

• The Welsh Coal Mines list of disasters gives 23 killed. The Wikipedia article on the village says the 1876 explosion killed 16 men and boys. The two have not been reconciled. (disputed)
• It was the last and worst of four underground explosions recorded at the colliery between 1857 and 1876. (uncertain)

Darran Colliery Explosion, 1909

• Twenty-seven men were killed, five of them members of a rescue party. (uncertain)
• Until the explosion the mine was considered safe, and throughout its history it had been worked with naked lights. (uncertain)
• With the winding shaft rendered inoperable by blast damage, a carpenter named William Evans descended the ventilation pit by a ladder fixed to the side of the shaft, found two injured men at the bottom, climbed back to the surface for help and returned with two others to get them up. (uncertain)
• A rescue party descended the connected Gilfach shaft equipped with breathing apparatus, but the capacity of their oxygen tanks proved inadequate and five of them were overcome by the toxic gases. (uncertain)

Digby Colliery Explosion, 1928

• The survivor said the coal-cutter men had worked for months without a flame safety lamp because the lamp cabin would not issue them; the lampman and manager said lamps were plentiful and had never been asked for. (disputed)

Diglake Colliery Inrush, 1895

• Staffordshire Past Track and the Bignall End memorial give 78. (disputed)

Disappearance of Thomas Severn, Mapperley Colliery, 1918

• Hector Tyler's 2007 book concluded Severn was most likely accidentally entombed in old workings after a hurriedly built stopping; Dr Robert Bradley's 2024 account suggested he had gone to examine an old gate road for gas. Neither is confirmed; the 1918 Inspector's report itself could not rule accident out or in. (uncertain)

Duffryn Main Colliery explosion, 1896

• Welsh Coal Mines says about 185 went underground that morning and 175 were raised between 10.45 and 11.05; the CMHRC account says 176 were out, leaving 20 still down. (disputed)

Easton Colliery explosion, 1886

• The BBC describes the eight as men aged between 22 and 45; the Coal Mining History Resource Centre list gives Charles Bryant as 21. (disputed)

Elba Colliery explosion

• Welsh Coal Mines says a defective lamp was held responsible for the explosion. The Durham Mining Museum gives the cause as an explosion of firedamp with the ignition caused by contraband. The two are not the same thing: a defective lamp is a failure of equipment, contraband is a man taking below what he should not have. (disputed)
• Welsh Coal Mines names eleven: Alec Ogilvie 20, William Bowen 17, William Davis 59, Tom Pratt 19, Edward Rees 26, David Davis 26, George Williams 14, David Rees 21, George Rees 23, W. H. Morgan 18 and John Long 45. The Durham Mining Museum lists ten of the eleven, giving Bowen as 18, Davies as 60, Pratt as 18 and Morgan as 20, and has no entry for John Long. Both agree the youngest was George Williams, a door boy of fourteen. (disputed)

Elliot Colliery Cage Fall

• A second account gives a different immediate mechanism: a large spanner being carried in the cage caught a 'bawk' (a supporting beam) as the cage approached the top, which pulled the winding rope out of its cap and sent the cage falling to the bottom of the shaft. Ages are also given slightly differently in this account — Davies 53 and Roberts 33, against 54 and 36 in the other source. (disputed)

Exhall Colliery fire

• The Durham Mining Museum lists all fourteen with their ages and gives the youngest as Sidney John James Beasley, fourteen, of Oak's Yard, Longford Road, Foleshill, and the oldest as William Henry Smith, fifty-seven, of Windmill Lane, Foleshill, with an average of thirty-four. Our Warwickshire says the dead were aged twenty-one to forty-seven. The museum's list is itemised and the Our Warwickshire figure is not. (disputed)

Falla Hill Colliery fire, 1902

• The Durham Mining Museum names the fireman killed in the 1902 fire as Robert Kilpatrick, aged 57. The Scottish Mining Website's index of 1902 deaths, compiled from the Inspector of Mines returns, gives the same man's age and occupation but names him James Patrick. The other three — John Russell, 32, brusher; Adam Cook, 16, drawer; and James Pettigrew, 42, brusher — agree between the two. (disputed)

Felling Colliery explosion, 1812

• The Durham Mining Museum and the Tyne and Wear HER both give 92 dead. The contemporary account the museum reproduces says ninety-one perished, and the obelisk at Heworth carries ninety-one names; the difference is most likely the three men who were brought out alive and died afterwards. (disputed)
• The explosion is dated 25 May 1812 by the contemporary account and by the museum's own record; the Tyne and Wear HER gives 24 May. (disputed)
• No cause was ever established with certainty. Firedamp ignited by a naked light is the probable one, there being no evidence of large quantities of coal dust in the air before the blast. (uncertain)

Felling Colliery explosion, 1847

• Wikipedia, citing the Newcastle Guardian of 26 June and 3 July 1847, dates the explosion to shortly after 9 p.m. on Tuesday 22 June 1847. (disputed)
• The Tyne and Wear Historic Environment Record gives 22 January 1847. (disputed)

Fforchaman Colliery explosion

• Welsh Coal Mines names the dead as William Williams, 30, collier; Lewis Griffiths, 48, collier; and David Evans, 45, roadman. The Bristol Mercury's report, quoted by the Northern Mine Research Society, gives the surnames as Griffiths, Evans and Lewis, which is the same three men with Lewis Griffiths's forename read as a surname. (disputed)
• Welsh Coal Mines dates the explosion to 5 January 1869. The Bristol Mercury report the Northern Mine Research Society quotes is dated 13 February 1869 and describes the explosion as having happened on 'Tuesday morning', which does not fit a 5 January date and suggests the newspaper was reprinting an earlier account. (disputed)

Fforchaman Colliery runaway drams

• Both accounts name Gwilym Williams, 15. Welsh Coal Mines gives the second boy as John Jones, 15, and so does the Northern Mine Research Society's own list of fatalities at the pit, which records Gwilym Williams crushed by trams and John Jones run over by trams on the same day. The Liverpool Mercury report the society quotes calls him John Thomas. (disputed)

Fordell Colliery boiler explosion, 1876

• A specialist secondary source records a fifth fatality under the name 'May Cook', not corroborated by the contemporary newspaper account, though consistent with that account's report of a badly scalded survivor not expected to recover. (uncertain)

Garden Pit Inundation, Landshipping, 1844

• Welsh Coal Mines records that the usual seepage suddenly increased in volume, that the miners were concerned enough to leave the mine, and that they were sent back after being reassured all was well, the sea breaking in an hour later. The Coflein account does not mention this and gives the time as about half past three. (disputed)
• The water is reported to have risen at seven fathoms — forty-two feet — a minute. (uncertain)
• The memorial erected by villagers in 2002 lists seven names where the first is given only as 'Miner'. These are believed to be women and children, although an Act of Parliament of 1842 had prohibited women and boys under ten from working underground. (uncertain)

Garnant Colliery Disaster, 1884

• The Welsh Coal Mines colliery page states that ten men met their death and names ten, and the local history site devoted to the disaster is dedicated to the memory of the ten. The Welsh Coal Mines list of disasters gives 18 for the same date; that figure is not followed here. (disputed)
• The men had arranged to start their shift before time so that they could attend a funeral after an early finish. (uncertain)
• An official was prosecuted for negligence over the accident; the mine owners themselves went unpunished. The colliery was at the time owned by David Pugh, MP for Cardiganshire. (uncertain)

Garngoch Colliery explosion, 1880

• Welsh Coal Mines' 1880 list gives the third man as Thomas Hugh Walters, noting that some give his surname as Hugh, and says he died of his injuries on the 15th; the Durham Mining Museum lists Thomas Hugh, killed on 7 July. (disputed)

Gellyceidrim Colliery runaway journey, 1897

• The Durham Mining Museum gives John Lloyd as a haulier; Welsh Coal Mines' 1897 list gives him as a collier. (disputed)

Gethin Colliery explosion, 1865

• An explosion in the Upper pit on 20 December 1865 killed 34 men and boys. (disputed)
• The 1865 toll is given as 36 elsewhere. (disputed)

Gill Head Colliery fall of stone, 1872

• The company at the colliery at the time of the accident is recorded as M. Laycock. The colliery’s own owner list gives Lucock & Carlton for the 1860s; whether these are the same name differently written has not been established. (uncertain)

Gin Pit explosion, 1863

• Welsh Coal Mines names the dead as William Elias (27, married); Dafydd Williams (44, wife, three children and a widow); Dafydd Williams (his 14-year-old son); Denis Mahany (14); William Gower (11); Benjamin Rees (17); Dafydd John (31, widow); John Bevan (53, of Ty'ncornel, wife and three children); William Davies (23, widow); William Isaac (38, carpenter, wife and seven children); David Jones (21, widow); Morgan Thomas (22, widow); Daniel Edwards (29, wife and two children); and Dafydd Rhys (38, married). (disputed)
• NMRS names the dead as William Isaac (40, married); Morgan Thomas (21); Benjamin Rees (17); David Williams (44, married); David Williams (14, his son); David Rees (36, married); Dennis Mahoney (14); David Jones (21); William Davies (23); David John (30); Daniel Edwards (25, married); John Bevan (41, married); and William Elias (27, married) — thirteen named against Welsh Coal Mines' fourteen, with several ages differing (Isaac 38/40, Edwards 29/25) and 'Dafydd Rhys' against 'David Rees', most likely the same men under anglicised or differently rendered names. (disputed)

Gleision Colliery Flooding, 2011

• The Written Ministerial Statement of 10 October 2011 describes the immediate cause as the failure of a retaining wall at the drift mine, releasing water into the workings -- a slightly different framing from other accounts describing a controlled blast breaching into flooded workings; both describe the same event, that a barrier separating the workings from a large body of water gave way. Sources also disagree narrowly on Philip Hill's age: 44 (Wikipedia) versus 45 (the Written Ministerial Statement). (disputed)

Glencraig Colliery explosion, 1902

• The Scotsman report reproduced by the Benarty Heritage group calls Marshall a widower of twenty; the Inspector's returns give him as 25 and Adamson as 26. (disputed)

Glyn Pits explosion, 1864

• Welsh Coal Mines: a length of timber left propping open an air door by the young door-boy caused the loss of ventilation. (disputed)
• Durham Mining Museum: both doors on the heading were left open by the haulier William Hill, himself among the dead, cutting the fresh air off the face entirely. (disputed)

Glyncorrwg Colliery Explosion

• The Welsh Coal Mines account states that after this explosion 'the use of aluminium at the coalface was prohibited'. The Inspector's actual recommendation was narrower: that light-alloy bars be prohibited on longwall faces with open wastes unless inflammable gas was known to be unlikely there. (disputed)

Graig Merthyr Colliery explosion, 1909

• The second man is Edward Mandry on the Welsh Coal Mines colliery page, Edward Mandray in the NMRS account, and Edward Mainwaring, a married man of Felindre, in Welsh Coal Mines' 1909 list. (disputed)

Grassmoor Colliery Explosion, 1933

• A local history of the colliery gives eight men injured rather than the four reported to the Commons. (disputed)
• The cause of ignition was uncertain, the Durham Mining Museum recording it as possibly an electric cap-lamp headpiece. (uncertain)

Greenrigg Colliery pithead fire

• Canmore's inventory entry (Oglethorpe 2006) records a pithead fire in 1925 that destroyed all the surface buildings. (disputed)
• The Wikishire account of Harthill, drawing on Lightbody's Harthill Through the Years (1997), dates the fire to 1924 and says it destroyed most of the surface buildings and the headframes. (disputed)

Grove Pit Disaster, 1930

• The explosion is believed to have been triggered by a naked light; five of the dead were found carrying contraband matches or cigarettes, though the inquiry could not establish with certainty who or what ignited the gas. (disputed)

Gwaun Cae Gurwen Colliery shaft accident, 1847

• The Cambrian of Friday 3 September 1847 describes the accident as happening at three on the Wednesday morning, 1 September; Welsh Coal Mines dates it September 1847. (disputed)
• The Durham Mining Museum lists a shaft accident with six lives lost on 31 August 1847. (disputed)
• Welsh Coal Mines' own summary says a flat winding rope broke; the Cambrian report it reproduces says a link of the chain, with a small flaw, broke. (disputed)

Gwendraeth Colliery Inundation

• Twenty-six men and boys died. Contemporary reporting records 27 on the night shift with one survivor, David Evans; some later summaries give 27 dead. (disputed)
• The two surviving name-lists disagree: Welsh Coal Mines gives Stephen Jones and Joseph Williams where the London Times of 18 May 1852 gives Stephen Phillips and Thomas Morris, and the two differ on several of the ages. (disputed)
• The inquest recorded an inundation of unknown cause. Contemporary press denied that the water came from the canal and attributed it to an old working being holed. (uncertain)

Harraton Colliery explosion, 1808

• DMM records '4+ lives lost'; NMRS's account names the overman Thomas Defty and three others as killed, with fourteen more burnt, some of whom may not have survived -- the eventual toll was likely higher than four but is not precisely established. (uncertain)

Harraton Nova Scotia Pit Chokedamp Deaths, 1817

• Eight lives were lost. Six bodies were recovered dead on the following day and two men were still alive, with little hope of recovery; all eight were recorded as buried on 5 July. (uncertain)
• Chokedamp, understood to have entered the Nova Scotia workings from the Row Pit after the explosion of two days earlier. (uncertain)
• Another party of men went down to look for them but were obliged to return without effecting their object, unable to proceed on account of the great quantity of chokedamp. (uncertain)

Harraton Row Pit Explosion, 1817

• Richardson's contemporary account says the accident was caused entirely by the perverse obstinacy of a hewer named John Moody, who in defiance of the overman's orders refused to use Davy's lamp and lit a candle, which was twice put out by the workmen he was relieving, and which he re-lit by unscrewing the lamp. A later account has Moody ordered to extinguish the candle and doing so, being found with a candle again and reprimanded, then extinguishing it and lighting his lamp — with the overman having just left him when the explosion occurred. (disputed)
• Thirty-eight men and boys were killed; the Wikipedia account gives them as 38 of the 41 men underground. (uncertain)
• Among the dead were ten belonging to one family, of the name of Hills — the grandfather, his two sons and seven grandsons. (uncertain)
• Corves, trams and several utensils used at the bottom of the shaft, 82 fathoms deep, were blown into the air, together with the bodies of two of the workmen — one with the head off, the other cut in two. (uncertain)
• All the dead except one from Fatfield belonged to New Painsher and were buried there on Wednesday 2 July. (uncertain)

Hebburn Colliery Explosion, 1805

• Between 32 and 35 men and boys were killed, leaving 5 widows and 81 orphaned children. (disputed)
• Durham Mining Museum's own colliery page independently lists this explosion, giving 35 lives lost but dating it to 6 October 1805 rather than the 21 October 1805 given by NMRS's dedicated disaster page — both figures are kept rather than one being silently preferred. (disputed)

Hetton Downs Pit Explosion, 1836

• Twenty were killed and another so dreadfully scorched as to afford but faint hopes of his recovery. (uncertain)
• Upwards of a hundred persons were employed in the pit at the time, but because the accident was confined to the Downs pit the number of victims was less than might have been expected. (uncertain)
• From the evidence at the coroner's inquest it appeared that the explosion was caused by the negligence or inattention of a boy who had charge of a trap door, whose duty was to keep it shut as much as possible so that the part of the pit where the men were working might be purified by a current of air. (uncertain)
• Several witnesses experienced in the management of mines, including George Hunter of Painsher, viewer to the Marquess of Londonderry, left no doubt that the general ventilation of the pit was excellent. (uncertain)
• The whole of the evidence tended to show that had the men been working with the Davy lamp instead of candles no explosion would have occurred; but it was stated that the men, even where danger existed, had an antipathy to the lamp because candles gave a better light. (uncertain)

Home Farm Colliery inundation, 1877

• The Falkirk Herald reported an eight-acre subsidence forty feet deep; The Times reported about a hundred feet over about a mile and 400,000 cubic yards of sand and gravel. (disputed)

Houghton Main Colliery explosion, 1930

• NMRS names seven dead: Albert Holden, James Lackey, Jacob Newberry, Norman Nicholson, John Pearson, William Richards and Charles Watson. A local-history account of the same explosion instead gives five dead and a date a week later. (disputed)

Jamage Colliery explosion, 1876

• The fireman is John Sharples in the Coal Mining History Resource Centre account and William Sharples in the newspaper account on Healey Hero. (disputed)
• One of the dead is Patrick Cogan or Cadam in the Coal Mining History Resource Centre account and Patrick Oadam, 37, in the newspaper account and the Durham Mining Museum list. (disputed)

Jamage Pit explosion

• Accounts differ on what warning there was. One has the manager discovering a trace of gob stink on the Friday, although no fire was seen. Amos Daniels, the manager, told the inquest that he examined the whole of the goaf and found no heating and no gob stink, and that he and the overman concluded any heating was due to pressure. (disputed)

Keppel Cove dam burst, 1927

• The Patterdale Parish Council account dates the dam burst to the night of 28–29 October 1927; the Patterdale PAST account instead gives 4 November 1927. (disputed)
• Compensation claims against the mining company were later put at over £4,500 by one account and over £25,000 by another. (disputed)

Kingswood Colliery boiler explosion, 1851

• A Kingswood Town Council history of the coalfield lists 'Starveall Engine Pit (later Speedwell Pit)' among the pits of the Kingswood collieries. (uncertain)

Leadhills (Minehill) suffocation, 1817

• One local account records that after the disaster “work never went on with spirit” at the Minehill workings. (uncertain)
• The pumping engine involved was a Watt-type engine originally reassembled at Minehill in 1788 by Robert Muir for the Leadhills Mining Company, a job judged poor enough that William Symington was later engaged to correct it. (uncertain)

Leeswood Main (Flue Pit) Inundation, 1864

• The colliery list and the Pontblyddyn burial register differ on four of the eight — John Smith at 22 or 23, John Jones at 19 or 23, Thomas Ellis at 15 or 16, and Lewis Lloyd at 47 or 48. (disputed)

Llanbradach Colliery Explosion, 1901

• The inquest evidence records all forty-one horses in the stables found dead, the heaviest trace of firing nearest the stable door. Welsh Coal Mines gives forty-three. (uncertain)
• A tradition recorded locally holds that a robin had nested in the underground pump room some weeks before the explosion, a wild bird underground being taken in the South Wales coalfield as a warning of disaster. Recorded as tradition, not as fact. (uncertain)

Llanerch Colliery Explosion, 1869

• Seven men were killed: William Cook, bottom cutter; Alfred Davies, collier, 30; John Jones, collier, 53; David Rees, collier, 30; Evan Rees, collier's helper, 15; Hananiah Williams, collier, 31; and Thomas Williams, bottom cutter, 27. (uncertain)
• The explosion took place at the Middle sinking pit, in the No. 1 deep heading of the Meadow Vein seam. (uncertain)
• The Monmouthshire Merlin describes Evan Rees as a lad of about fourteen working with John Jones; Welsh Coal Mines gives his age as fifteen. (uncertain)

Llanhilleth Colliery fall of coal, 1907

• Welsh Coal Mines says a 'bumper' shook the place where they were working, filling a dram, and brought down the coal. (disputed)
• The Inspector's report, as given by the Durham Mining Museum, says the coal in the Black Vein, about 7½ feet thick, was worked on the face slip and overhung about a yard; the lump that fell, seven feet across and loose at both ends, was held by only one sprag, which was totally insufficient. (disputed)
• William is William George Morgan, 25, in Welsh Coal Mines and William Morgan, 28, in the Durham Mining Museum; Walter is 20 in both. (disputed)

Lletty Shenkin Colliery Explosion, 1849

• The Durham Mining Museum dates the explosion 11 August 1849 — the day the inquest opened — and the Welsh Coal Mines colliery page gives 14 August. (disputed)

Lluest Colliery Explosion, 1899

• Nineteen men and boys were killed. (uncertain)
• One of the victims, William Thomas of Tydu, was overcome by afterdamp after leaving another part of the mine to attempt a rescue of the stricken men. (uncertain)

Lofthouse Colliery disaster, 1973

• The Mines (Precautions Against Inrushes) Regulations that followed are dated 1979. (disputed)
• The same regulations are dated 1978 elsewhere. (disputed)

Lundhill Colliery explosion, 1854

• The NMRS names James Batty, 32, banksman; William Davis, 50; Matthew Thompson, 50; Thomas Jackson, 48; and Noah Ely, 52. (disputed)
• The Durham Mining Museum names six: James Batty, 23, banksman; William Davey, 50; Noah Heeley, 52; Thomas Jackson; William Mosely, 24; and Matthew Pollard, 50. (disputed)

Maerdy Colliery explosion, 1885

• NMRS's dedicated accident page gives 76 deaths; Wikipedia separately gives 81. Both figures are recorded rather than reconciled. (disputed)

Marine Colliery explosion, 1927

• Reported predominantly as 52 men killed (NMRS disaster page, welshcoalmines.co.uk); an NMRS overview page separately gives 51 — kept as an unresolved minor discrepancy rather than silently rounded. (uncertain)

McLaren Colliery Explosion, 1902

• Seventeen men were killed in the explosion of 3 September 1902. (uncertain)
• The death roll records addresses in the new village of Abertysswg — McLaren Cottages and Arthur Street — and in Tredegar and Cwmsifiog down the valley. (uncertain)
• The youngest of the dead was William J. Jones of 30 East Street, Tredegar, aged seventeen. (uncertain)

Middle Duffryn Colliery explosion, 1850

• On 12 December 1850 a roof fall released gas which was fired at a naked candle; eight died at once, including a man on the surface killed when the blast smashed the staging he stood on, and five more died later of their injuries. (disputed)
• The contemporary report reproduced in the Cynon Valley compilation lists eight dead, four killed on the day and four who died of burns by the 19th, and eight named survivors badly burned; the same eight names head the Welsh Coal Mines death roll. (disputed)

Middle Duffryn Colliery Explosion, 1852

• The Welsh Coal Mines colliery page dates the explosion 15 May 1852, against its own death roll and the contemporary newspapers. (disputed)
• Welsh Coal Mines describes the nine as killed when a wooden platform they had gathered on in the pumping shaft collapsed to the pit bottom; the Monmouthshire Merlin's account has the bottom ladder of the descending shaft broken away, with three or four dead found at its foot. (disputed)

Milfraen Colliery cage accident, 1902

• On 4 March 1902 a cage in which men were ascending the 250-yard shaft touched some ironwork and tipped five of them out to their deaths, among them a father and son, David and Edward Stollard, who had begun work at the colliery that same morning. (disputed)
• The Durham Mining Museum, from the 1902 Inspector's report, names the five as Elias James Griffiths, 13, and Elias T. Griffiths, 48; David Phillips, 37; and Edward Stallard, 53, and William A. Stallard, 15. (disputed)

Milfraen Colliery explosion, 1929

• The Durham Mining Museum dates Ernest Southcott's death to 29 July 1929; the eyewitness account on Welsh Coal Mines says he died eight days after the explosion. (disputed)

Morfa Colliery explosion, 1858

• Welsh Coal Mines dates the explosion 26 November 1858. (disputed)
• The Durham Mining Museum dates the four deaths 25 November 1858. (disputed)
• The Welsh Coal Mines colliery page names the fourth man John Williams; its death roll and the Durham Mining Museum name him William Williams, 24, single. (disputed)

Morfa Colliery explosion, 1863

• The NMRS account gives thirty-eight dead of the forty-three in the heading. (disputed)
• Welsh Coal Mines names forty dead in its death roll. (disputed)
• A page on the 1890 disaster says 30 were killed in 1863. (disputed)
• The NMRS account has the manager William Grey knocked down, leading a search party and giving evidence afterwards; the Welsh Coal Mines roll lists William Grey, 46, the manager, as having died later. (disputed)

Morfa Colliery explosion, 1870

• The manager, Mr Gray, believed the store of blasting powder near the shaft bottom had exploded. (disputed)
• The inquest jury, fifteen to two, found an explosion of firedamp in the west stables, with no one to blame. (disputed)
• Inspector Wales concluded that gas dammed in a 40-acre goaf since the previous August forced its way through the stowing and down a staple to a naked light or the gas light at the shaft bottom. (disputed)

Morfa Colliery explosion, 1890

• The official reports and the General Register Office index record 87 dead, including the explorer Daniel Brownsell. (disputed)
• Welsh Coal Mines' account gives 89 dead including one of the rescuers. (disputed)

Mostyn Colliery Inundation, 1884

• Accounts differ on the day: Heritage Hunter gives the evening of 22 July 1884, while another account gives 19 July. The Flintshire Observer reported the event on 24 July 1884. (disputed)

Nantymwyn dynamite explosion, 1892

• A local-history account describes the dynamite box slipping and exploding while being lowered down the shaft, with the men dying of shock-induced heart failure. (disputed)
• A contemporary newspaper account instead describes the box being opened at the 24-fathom level, with only part of its contents detonating and the rest burning to release toxic fumes, which is given as the actual cause of death. (disputed)

Naval (Pen-y-Craig) Colliery explosion, 1880

• The explosion killed 101 men and boys per most sources; one contemporary inspector's report gives 110, a genuine period discrepancy. (disputed)

New Tredegar Colliery Explosion, 1875

• At the inquest it was suggested that William Evans, a father of twelve children who had watched his family suffer through a recent long strike, was desperate not to lose any more time from work because of his financial difficulties. He was himself among the dead, so the matter could not be put to him. (uncertain)

Old Coal Pit Explosion, Coalbrookdale (1856)

• The Durham Mining Museum's own transcription of the original 1856 report states 10 men were killed, one fewer than NMRS's list of 11 named victims, and gives the operating partnership as 'Cruttwell and Levick' rather than 'Couttwell and Lewis' -- most likely the same names garbled differently by transcription in each source, since DMM's individual record for George Morgan (28, roadman) matches NMRS's named victim exactly. (disputed)

Pantyffynnon Colliery explosion, 1908

• The colliery page describes William Roberts as a collier of Hopkinstown; the 1908 fatality list gives him as 52, a collier of Ammanford. (disputed)

Parys Mountain boiler explosion, 1870

• One page of the Parys Underground Group's own site gives one confirmed death with 8–10 injured (three critically); a separate page on the same site instead states the explosion killed seven men. (disputed)

Pelsall Hall Colliery inundation, 1872

• Charles Starkey told the inquest he helped rescue nine men, including two of his sons, from water already seven to eight feet deep in the shaft. (disputed)

Pendleton Colliery explosion, 1870

• The NMRS account dates the explosion to 6 February 1870. (disputed)
• The Durham Mining Museum dates the explosion to 4 February 1870, with Joseph Ashton dying of his injuries on 11 February. (disputed)

Pendleton Colliery Floor Heave, 1925

• Six men died: Samuel Corbett, Stephen Morris, Edward Ditchfield, Frank Bramwell, Robert Hanrahan and Radcliffe Holden. A separate 2024 news source states eight deaths for the same incident. (disputed)

Pentre Colliery Explosion, 1871

• Thirty-eight men and boys were killed. The source notes that some accounts claimed 41, but that 38 appears to be correct, and lists 38 names. (uncertain)
• The force of the blast caused extensive damage to the headgear, allowing only one side of the pit to operate. (uncertain)
• A rescue party of five men descended the shaft, but as soon as the cage reached the pit bottom they were overcome by the effects of afterdamp. Two of them succumbed and are numbered among the dead. (uncertain)

Pretoria Pit Disaster

• The NMRS account, following the inspectors’ recovery figures, gives approximately 345 deaths once a man killed in the Arley mine and one who died fighting a surface fire are included. (disputed)
• Wikipedia’s account places the explosion in the Plodder mine and attributes it to an accumulation of gas released by a roof collapse the previous day. (disputed)

Queen Pit Explosion, 1868

• Of around 26 men working in the affected area, only two escaped unhurt; sources give the confirmed death toll as either 26 or 23-24, with a small number of survivors later dying of their injuries. (disputed)

Rhigos Colliery Explosion

• The two accounts disagree on the age of Dan Jones junior: the colliery page gives 38, the 1941 fatality list gives 16 and records him as the son of Dan Jones senior, aged 65. (disputed)

Risca New Pit Explosion, 1880

• A change to three shifts and to extraction methods had worried the miners, who believed the face was moving forward too fast and that gas was not being dispersed sufficiently. (uncertain)
• Deputies used the Davy lamp for their inspections, but the colliers preferred the older Clanny because it gave a better light. Davy himself had doubted the Clanny's safety because its gauze was unprotected against strong air currents; his view was later borne out and the lamp was banned from mines. (uncertain)

River Level Colliery inrush, 1896

• NMRS gives Thomas Jenkins's age as 14; Welsh Coal Mines gives 18. All other names and ages agree between the two accounts. (disputed)

Seaham Colliery Explosion

• The NMRS account, itemising the dead by occupation, gives 161 killed of 231 underground. (disputed)
• Several accounts, including the local commemoration, give the toll as 164 men and boys; Wikipedia says "upwards of 160", including surface workers and rescuers. (disputed)
• The inquest heard three competing explanations — gunpowder shots fired by the Venner brothers, paraffin lamps at the main coal staple bottom, and an origin at the staple bottom itself — and did not decide between them. (uncertain)

Seaham Colliery Explosion, 1871

• Durham Mining Museum's own record gives the date as 25 October 1871 (with a matching 11:30pm timestamp on individual victims' entries) and attributes ignition to a naked light, while NMRS's account gives 21 October and attributes ignition to a blasting shot fired by stoneman Thomas Hutchinson; the underlying outburst-of-gas event and 26-death toll are consistent across both. (disputed)

Seven Sisters Colliery Explosion, 1907

• The explosion was caused by a defective safety lamp. (uncertain)
• The Wikipedia account describes the incident as a blow-out, the sudden outburst of gas to which anthracite coalfields are prone. (uncertain)

Six Bells Colliery explosion, 1960

• A National Union of Mineworkers inspector, A. Davies, argued that a shot fired in the ripping ignited the gas; the inquiry rejected this because the direction of flame did not support it. (disputed)
• The inquiry report gives 1,213 men employed below ground and 239 on the surface, and about 1,800 tons of saleable coal a day; Wikipedia gives 1,291 men and 338,000 tonnes for 1960. (disputed)

Snaefell Mine disaster

• The Northern Mine Research Society gives a death toll of 23; other secondary accounts give 19-20. (disputed)

Sneyd Colliery Explosion

• Fifty-five were killed outright and two died in hospital, a total of 57; the Durham Mining Museum's colliery page records 55. (disputed)
• The inquiry under Sir Henry Walker found that derailed tubs damaged an electric cable and the sparks ignited coal dust; the Durham Mining Museum records friction between the ascending rope and a descending tub, and later writers have blamed a snapped steel rope or the empties striking the compressed-air pipe. (disputed)

Springwell Colliery Explosion, 1833

• Forty-seven were deprived of life instantly, besides many who received severe fractures and contusions. Only nine or ten of the dead were adults; the remainder were boys. (uncertain)
• By seven o'clock on the night of the following day only eight bodies had been recovered; thirty-nine remained in the mine. (uncertain)
• The mine had been examined by the under viewer and overmen that morning and declared quite safe. About eight a.m. an overman saw that a collier had pricked a blower and ordered him out of that part of the mine; returning two hours later with the under viewer he saw no danger, but as a precaution ordered safety lamps to be used instead of the candles the mine had been worked with, owing to the extreme purity of the air. (uncertain)
• A garbled account printed and hawked about Newcastle charged an unfortunate stranger, said to be a Welshman, with having caused the explosion by taking the top off his safety lamp. The coroner had Thomas Turner of Staffordshire examined for his exculpation; Turner said he had used a Davy lamp, had never taken the top off one in his life, and that the report was unfounded. (uncertain)
• The jury returned a verdict of accidental death. (uncertain)
• The accident occurred in the Hetton seam, at a depth of 120 fathoms. (uncertain)

Springwell Colliery Explosion, 1837

• Of twenty-nine men and boys at work in that part of the Hutton seam, twenty-seven perished — fifteen men and twelve boys. Three horses were also killed. (uncertain)
• The depth of the pit to the Hutton seam was 128 fathoms, the seam dipping east at a decline of one foot in sixteen. (uncertain)
• Every available means had been adopted to improve the ventilation after the earlier accident, the most expensive being a communication driven from the Springwell pit to another shaft on the Black Fell, the former the downcast and the latter the upcast. The pitmen did not consider the pit at all fiery. (uncertain)
• The workings ran both the whole coal and the broken. The broken — where the supporting pillars are removed and the roof held temporarily on props — was always reckoned the most dangerous, and safety lamps were used exclusively there, the men being supplied with locked lamps as they went down. When working the unbroken seam the custom was to blast it with gunpowder, and for that the men used candles. (uncertain)
• The safety lamp of Edward Price was found near traces of fire in the broken workings, positioned as though it had fallen across the rolley way and been accidentally run over. Its gauze and glass were broken and much bulged in, and Price's body lay not far off. The lamp was identified by its number, and the witnesses' opinion was that its breaking caused the fire. (uncertain)
• The jury, after a few minutes' consultation, returned a verdict of accidental death. (uncertain)

St David's Colliery explosion, 1840

• Welsh Coal Mines dates the explosion 27 June 1840, and the Glamorgan, Monmouth and Brecon Gazette of Saturday 11 July 1840 reports it as 'on Saturday week'. (disputed)
• The Durham Mining Museum lists the explosion under July 1840 and gives 6 July 1840 as the date of death of five of the dead, David Samuel dying on 15 July. (disputed)

Trimdon Grange Colliery Explosion, 1882

• Lower figures are also in circulation: a contemporary description of the colliery reproduced by the Durham Mining Museum gives 71 killed, and 69 appears in other accounts. No source located explains how the smaller totals were arrived at; the disaster killed men on both sides of the underground connection with East Hetton, which may account for some of the variation. (disputed)

Tynewydd Colliery inundation, 1877

• Welsh Coal Mines names the two drowned in the first inrush as John Hughes, 50, and his son William, 18; the police list put to the inquest names John Hughes, found on 30 April, and William Jones, found on 1 May. (disputed)

Ubberley Colliery explosion, 1851

• The museum and the Newcastle Guardian of 23 August place it on Monday 18 August 1851; the Healey Hero transcription is headed 25 August. (disputed)

Udston Colliery explosion, 1887

• A watch on the body of the fireman Alexander Torley had stopped at 9.07 a.m., and Wikipedia gives the explosion as about 9.07. (disputed)
• The NMRS account gives the time as about 9.15 a.m. (disputed)
• H.M. Inspector Ralph Moore concluded it was a coal dust explosion started when a shot fired surreptitiously ignited a little gas, probably in the Rise section at Dennison's place. (disputed)
• The inquiry by J. Dickinson and C. C. Maconochie found it most likely began in the stooping of the West or Blantyre section, or at Harkness's shot in the east, from firedamp ignited at an open light, a match or through a Scotch lamp gauze, reinforced by gas and dust. (disputed)

Underwood Colliery fire

• George Ball, a stallman, and John Smith, a hanger-on, both of Cordon Lane, Brinsley. The Nottingham and Counties Daily Express of 21 April 1874 gives their ages as 37 and 22; the Durham Mining Museum gives 38 and 24. One family account on Healey Hero dates John Smith's death to 12 September 1874, which the newspapers and the museum both contradict. (disputed)

Upton Colliery Explosion, 1940

• The Derby Evening Telegraph of 5 June 1940 names six dead and eight burned. Hansard, reporting to the Commons the same day while the toll was still rising, gave two killed and one since died. A later secondary account states ten died; that figure appears to be a misreading of the Telegraph report and is not followed here. (uncertain)
• It was believed that a stopping which had sealed off an area where a fire occurred some months earlier had blown out. (uncertain)

Waunhir Slant runaway

• The two accounts name the same six men but differ on their details. Welsh Coal Mines gives Benjamin Davies, 32; Albert Henry Liley, 19; John Rees, 18; David Lodwig, 24; David Davies, 23; and Arthur Llewellyn Price, a collier's boy of 16. The Northern Mine Research Society gives Benjamin Davies, 30, of Waenyglyn; Albert Lilley, 18, of Kidwelly; John Rees, 16, of Capel; David Lodwick, 28, of Waenyglyn; David Davies of Pwll; and David Price of Trimsharan. (disputed)

Weigfach Colliery Explosion, 1877

• The Welsh Coal Mines colliery page says eighteen were killed and names eighteen; the same site's list of Welsh mining disasters gives 19. (disputed)
• Those named include Abraham Bevan, the overman, forty-eight, who left a wife and five children; the colliers Isaac Williams and David Williams, both with wives and young families; the trammers John Davies, sixteen, and William Williams, twenty; and Thomas Thomas, a widower of forty-six with two children. (uncertain)

Wellington Pit explosion, 1910

• The death toll is given elsewhere as 147, of whom 35 men and boys in the No. 5 and No. 6 Districts died without direct injury from the explosion. (disputed)

Werfa Colliery explosion, 1886

• Welsh Coal Mines' 1886 list dates the explosion Friday 26 March 1886, about 2.30 p.m., and the Pall Mall Gazette of Saturday 27 March reported it as having just occurred. (disputed)
• The Welsh Coal Mines colliery page dates the explosion 23 March 1886. (disputed)
• Four died: David Jones, 38, fireman; William Marshall, 45, labourer; John Green, 46, airway man; and William Edwards, 39, haulier, who died of injuries on 3 April. (disputed)
• The Pall Mall Gazette, quoted by the NMRS, reported three killed 600 yards from the shaft bottom, David Jones, foreman, William Marshall and John Green, with George Green severely burned. (disputed)
• The Pall Mall Gazette says the explosion was in the Seven Feet vein of the new pit and blew away the covering of the upcast shaft; Welsh Coal Mines' list places it in the downcast shaft (Seven Feet vein). (disputed)

Werfa Colliery shaft accident, 1851

• Welsh Coal Mines gives fourteen killed and names fourteen, though its colliery page also says eleven miners including three boys and puts three in the ascending cage while its 1851 list says two; NMRS says sixteen. (disputed)

Wernbwll Colliery explosion, 1929

• The owners' expert witnesses, mining engineers J. Dyer Lewis and John Kane, maintained the explosion was caused solely by coal dust ignited at an acetylene lamp flame in the No.1 tophole, with no firedamp involved; the Miners' Agent, D.L. Davies, thought coal dust the main agent but could not rule out firedamp; H.M. Inspectors of Mines Lea, Waldin and Finney, and the reporting Inspector, F.H. Wynne, concluded firedamp accumulated in the level was the primary ignition source, subsequently extended by coal dust. (disputed)

West Cannock No. 5 Colliery Explosion (1933)

• A House of Commons statement (17 May 1933) gave three dead and three seriously injured; other records of the same disaster give six dead. (disputed)
• The inquest's own final list names five dead (Gwilt, Cornwall, Turncock, John Henry Williams, Higgins), superseding the Commons' next-day preliminary count of three; the same source's own inquest-verdict paragraph separately implies a sixth victim (a second Williams brother, Joseph) not in its own headline list -- an internal inconsistency in the source, not resolved here. (disputed)

West Stanley Colliery explosion, 1909

• The dead numbered 167 by the per-seam count — 18 in the Tilley, 63 in the Towneley, 38 in the Busty and 48 in the Brockwell. (disputed)
• The death toll is given as 168 elsewhere, with 29 survivors. (disputed)

William Pit Explosion, 1839

• NMRS names 22 individuals and states the toll as nine men and twelve boys (21); CATMHS's separate colliery history gives 23. Both figures are preserved rather than one being silently chosen. (disputed)

Woodhorn Colliery explosion

• The Ashington Coal Company afterwards pressed the bereaved families to leave their company houses, threatening to withhold compensation. (uncertain)

Workington Colliery Inundation, 1837

• The Durham Mining Museum records 27 lives lost. Galloway notes the toll was 'variously stated at from twenty-seven to forty human beings, and an almost equal number of horses'. (disputed)

Yniscedwyn Colliery runaway, 1892

• The Northern Mine Research Society names six men killed in the 1892 runaway and three injured; the Durham Mining Museum's disaster listing gives seven lives lost. (disputed)
• The Durham Mining Museum lists seven dead, including Thomas Jeffreys, 18, whose name also appears in its list for a fall of roof on 5 November 1892. (disputed)
• The ages given differ: Thomas Sims 70 (NMRS, DMM) or 60 (Welsh Coal Mines), William Jones 30 or 40, Thomas Phillips 42 or 40. (disputed)

Ystrad Colliery Explosion, Glanamman, 1978

• One forum account dates the explosion to 1 May 1973; a former worker in the same thread put it at about 1978. (disputed)
• It was said locally at the time that the explosion was caused by men smoking in the return airway, though Dai Fish did not smoke. (uncertain)