Open questions: Neath Port Talbot

Where sources disagree, MineArchive keeps both accounts rather than picking one; where a fact could not be settled, the record says so. 76 such claims on 39 records. All regions.

Aberbaiden Colliery

• In 1923 the colliery employed 1,268, 1,076 of them below ground. (uncertain)
• Aberbaiden, Tytalwyn and Pentre slants closed in January 1959. (uncertain)

Abernant Colliery

• 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)

Avon Colliery

• The Ocean Coal Company took over the running of the colliery in 1911. (disputed)
• The Ocean Coal Company took over the colliery in 1912. (disputed)

Boundary Level

• 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)
• Thomas Richardson White, who also agreed sidings with the Midland Railway at Cwm Click in 1878, was the colliery's side of the 1882 agreement; the catalogue does not say whether he owned or leased the level. (uncertain)

Cambria Mercantile Colliery

• 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)

Cefn Coed Colliery

• 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

• 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)

Crynant Colliery

• 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)

Cwmceiros Colliery

• 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

• 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 accounts disagree. (disputed)

Cwmgwrach Colliery

• The Welsh Coal Mines page's main account credits the Caerbryn and Empire Collieries Co. Ltd with sinking the Empire colliery into the old Cwmgwrach level in 1903; Tony Cooke's notes on the same page have the upcast shaft sunk as part of the Blindells' reopening of 1898-99, with Caerbryn and Empire taking over only in late 1908. (disputed)
• 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

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

Cwrt Herbert Colliery

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

Duffryn Rhondda Colliery

• 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)

Elwyn Colliery

• 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)

Ffaldydre Colliery

• 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)

Garth Colliery, Tonmawr

• A National Coal Board broadsheet gives the opening date of Blaenmawr as 1864, but no record of it is found until 1917, when it was owned by D. Edwards and Sons. (uncertain)

Glyn Neath Colliery

• 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)

Glyncastle Colliery

• 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

• 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. No other account repeats it. (uncertain)

Graigola Colliery

• 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)

Gwaun Cae Gurwen Colliery

• 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)

Hendreforgan Colliery

• 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)

Lyn Colliery

• The Lyn Colliery Co. Ltd is recorded as owner in 1991. (disputed)

Maes Marchog Colliery

• 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)

Morfa Colliery

• 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)

Nant Hir Colliery

• 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)

New Wernddu Colliery

• 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)

Onllwyn Colliery

• 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)

Pentreclwydau Colliery

• NMRS records the ground being developed by thirteen men under manager E.J.H. Nicholas in 1947. (disputed)
• Welsh Coal Mines says work on site began in July 1954. (disputed)
• NMRS: 352 men and 45,000 tons in 1960; 513 men and 85,490 tons in 1961. (disputed)
• Welsh Coal Mines: 221 underground and 52 surface each year 1960-65, and 354/76 in 1966. (disputed)

Pwllbach Colliery

• 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)

Pwllfaron Colliery

• The anthracite slant was opened in 1866. (uncertain)

Rhigos Colliery

• 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)

Seven Sisters Colliery

• 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)

Tir Edmund Colliery

• 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)

Tynywain Colliery

• 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)

Upper Graigola Colliery

• The Upper Graigola Level was abandoned in 1923 by the Llwyn Du Colliery Company Limited. (disputed)

Wernffraith Colliery

• An abandonment plan titled Wernffraith, in the Wernffraith seam, is dated 1930. (uncertain)

Whitworth Colliery

• Whitworth Collieries Ltd was registered on 12 February 1905, passed into German-controlled directorship in October 1906, cut its first sod on 29 April 1907, and suspended sinking in November 1911 on the death of a Mr de Frietas. (disputed)
• One account has the works purchased in 1912 by the New Rhondda Collieries Limited and in 1913 by Baldwins Limited, who dismantled the surface equipment. (disputed)
• The same account elsewhere reports the plant as acquired by Messrs Baldwins in 1919, for their new pits at Margam and Aberbaiden. (disputed)