Glyn-nant-ddu Colliery

Overview

A shaft mine on the northern slope of the valley opposite Blaenserchan, near Abersychan, working the Tillery or Red Ash seam. It was probably at work by 1830, may have been water-powered, and employed over a hundred men in 1896 before it was abandoned in May 1904.

History

Glyn-nant-ddu was a shaft mine on the northern slopes of the valley opposite Blaenserchan Colliery, near Abersychan, sunk to work the Tillery or Brithdir seam, known here as the Red Ash. It is probably early: the Greenwood map of 1830 shows a pair of buildings on the site, and the pit was most likely already at work by then. A large building stood downslope of the shaft, and a feeder pond some 50 metres long lay above the colliery with a second pond below. The building's alignment makes a winding engine unlikely, and the pit may instead have been worked by a water wheel. Water-powered haulage surviving at a working colliery as late as about 1880 would be unusual in this district.

It was one of the 37 collieries worked by the Ebbw Vale Steel, Iron and Coal Company, and was still listed under that company in 1878, managed by J. Powell; the same year it is also recorded as owned by James and Emmanuel of Abersychan, with R. Emmanuel as manager. In 1896 it employed 105 men underground and 13 on the surface under E. Emmanuel, and 90 men in 1899. The 1901 Ordnance Survey map shows it as disused, though a small maintenance crew may have stayed on. It was abandoned in May 1904, its workings in the Red Ash recorded on one plan with neighbouring Cwm Nant Ddu.

Geology

The Tillery seam, also called the Brithdir and locally the Red Ash.

Workings

A shaft with a large building downslope and feeder ponds above and below, which suggest water-powered winding or haulage.

Closure

Shown disused on the 1901 Ordnance Survey map and abandoned in May 1904.

What remains

Unknown.

Redevelopment

Unknown.

What's uncertain

Points where sources disagree or the record could not be settled; both accounts are kept. All open questions in the archive.

• The 1830 Greenwood map shows buildings on the site, and the pit was probably at work by then. (uncertain) ¹

Recorded claims

Individual factual claims, each attached to the source(s) that support it below. Where sources disagree, both are kept.

• The 1830 Greenwood map shows buildings on the site, and the pit was probably at work by then. (uncertain) ¹
• In 1896 it employed 105 men underground and 13 on the surface. ¹
• It worked the Tillery seam, known as the Red Ash. ^1,2
• Glyn Nant Ddu was abandoned in 1904. ^1,2
• Glyn-nant-ddu appears on the Abersychan district plans with Cwmsychan, Big Pit, Cwmnantddu and Blaenserchan. ³

Photographs & further reading

Sources

1. (secondary) Welsh Coal Mines: Glyn Nant Ddu colliery — Welsh Coal Mines
2. (primary) BGS / Mining Remediation Authority mine plan: GLYN NANT DDU AND CWM NANT DDU, CWMBURGWM, abandoned 1904 — British Geological Survey
3. (primary) BGS / Mining Remediation Authority mine plan: ABERSYCHAN, CWMSERCHAN ... GLYN-NANT-DDU, CWMNANTDDU, BLAENSERCHAN — British Geological Survey

Record created: 10 October 2026 · Last researched: 10 October 2026