Open questions: Blaenau Gwent

Where sources disagree, MineArchive keeps both accounts rather than picking one; where a fact could not be settled, the record says so. 44 such claims on 22 records. All regions.

Beaufort Iron Works

• 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)

Bedwellty Pits

• 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)
• 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)

Beynon Colliery

• The colliery opened in July 1923: Out Of The Blue Artifacts gives the official opening as Friday 13 July with coal first handled through the screens on Monday 16 July, while the Northern Mine Research Society gives 14 July as the start of production. (disputed)
• In 1923 Beynon's, with the Lower Deep and North Blaina, employed about 1,427 men by the Welsh Coal Mines figure and 1,527 by the Northern Mine Research Society's, working the Big, Three Quarter, Black and Meadow Vein seams. (disputed)

Coalbrook Vale Colliery

• 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)

Coed Cae Tillery Colliery

• 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)

Cwmtillery Colliery

• 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)
• The colliery closed in 1982. (uncertain)

Erskine Colliery

• A licensed-mine plan of December 1980 covers the Swffryd or Sofrydd, Erskine and Cwm-llwy-nau levels in the Mynyddislwyn seam. (uncertain)

Forge Colliery, Nantyglo

• 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)

Gray Colliery

• The Black Vein was struck in June 1891 and the first coal raised in 1893. (disputed)
• The pit was sunk in 1894. (disputed)
• It was abandoned on 11 March 1950. (disputed)
• It was finally closed in 1938 and filled in 1959. (disputed)

Griffin No. 1 Colliery

• Sunk before 1873 by the Nantyglo and Blaina Company and taken over in 1878 by J. Lancaster and Company. (disputed)
• Sunk before 1868 by John Lancaster. (disputed)
• Closed around 1909. (disputed)
• Closed as a production unit when Beynon Colliery opened in 1922, and filled in 1957. (disputed)

Hafod Van Colliery

• The Hafod Van slope restarted the colliery in 1911 and employed 122 men that year and 79 in 1912. (disputed)
• The Hafod Van slope was opened in 1909, employed 122 men by 1910 and closed in 1914; a New Hafod Van slope was opened in 1922 and worked until 1928. (disputed)

Henwaun Colliery

• The Henwaun Pit was sunk in the early 1850s by Cruttwell, Allies and Co. to 165 yards to the steam coal seams of the Lower and Middle Coal Series, and was owned in 1857 by J. and C. Bailey to feed their ironworks. (disputed)
• Henwaun Colliery was sunk in 1856 to feed the Nantyglo Ironworks, passed to John Lancaster's concern in 1881 and closed in 1922. (disputed)

Lower Deep Colliery

• It was opened in 1860 by Lancaster's Steam Coal Collieries Ltd. (disputed)

North Blaina Colliery

• 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)

Penybont Colliery

• Messrs T. P. and D. Price reached the steam coal in November 1850. (disputed)
• It was sunk in 1851 by Jayne's Tillery Company. (disputed)

Pochin Colliery

• 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)

Rhiw Colbren Colliery

• In 1908 it employed 13 men under Thomas F. Salt. (disputed)
• In 1908 it employed 31 men. (disputed)

Rose Heyworth Colliery

• 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)

Six Bells Colliery

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

Victoria Colliery, Ebbw Vale

• The No. 6 pit at Victoria was sunk in 1838. (disputed)
• The No. 1 shaft was sunk to 690 feet and completed in 1846; No. 6 was added in 1847. (disputed)

Waunllwyd Colliery

• Waunlwyd closed in 1964. (disputed)
• All three shafts were sunk between 1874 and 1876. (disputed)

Whitworth Colliery (Tredegar)

• The No. 2 shaft was 182 yards deep and the No. 1 shaft 100 yards. (uncertain)
• The No. 2 pit was sunk to a depth of 337 feet 10 inches. (uncertain)