Lower Duffryn Colliery

Overview

Thomas Powell's steam-coal colliery at Cwmpennar, Mountain Ash, opened in the early 1850s and worked by Powell Duffryn from 1864. Explosions killed nineteen in 1858 and at least eight in 1860, and in 1910 a dispute over its customs set off a bitter strike across the Cynon Valley. Coal ceased in 1927.

History

Thomas Powell of the Gaer, near Newport, opened the Lower Duffryn, or Cwmpennar, colliery in the early 1850s, alongside his Cwmdare, Upper and Middle Duffryn pits. It had two shafts about 350 yards apart, the Upper (376 yards) and Lower (345 yards), both winding coal, first ventilated by furnace and wound by water balance. Explosions in February 1858 and November 1860 killed thirty-one men and boys between them (see Disasters, below). The Powell Duffryn Steam Coal Company became owners in 1864. In 1870 the pit employed 893 and raised 191,694 tons; it closed briefly in the slump of 1875. The Lower pit was deepened to the steam coal measures in 1888, and by 1914 worked the Gellideg, Seven Feet and Nine Feet seams with some 800 men. In 1910 the company's attempt to remove long-established customs brought the men out, the strike spread through most of the valley's pits amid riots, and the men returned defeated. Coal winding stopped in 1927, the colliery closed as a producing unit in July 1932, and it pumped water for the district until the 1970s.

Geology

South Wales Coal Measures: the Four Feet, Six Feet, Nine Feet, Five Feet, Seven Feet, Gellideg, Yard and Castell y Wiver seams.

Workings

Two shafts about 350 yards apart, the Lower later deepened to the Seven Feet at 348 yards with an elliptical section; a drift started in 1843 later connected to the pit.

Closure

Stopped working coal in 1927; closed as a production unit in July 1932; pumping ceased in the 1970s.

What remains

Unknown.

Unknown.

Redevelopment

Unknown.

Related mines

• Middle Duffryn Colliery — Neighbouring Thomas Powell pits in the Aberdare valley; their names overlap in the sources.

Nearby mines

• Deep Duffryn Colliery — 0.8 km SE
• Abercwmboi Colliery — 1.1 km SW
• Middle Duffryn Colliery — 1.1 km W
• Nixon's Navigation Colliery — 1.5 km SE
• Lletty Shenkin Colliery — 1.7 km NW

Straight-line distance, within 15 km. Show on the map.

Disasters & major incidents

• Lower Duffryn Colliery explosion, 1858
  1858 · Explosion · 19 fatalities
  At about two in the morning of 25 February 1858 an explosion of firedamp in the upper colliery of Thomas Powell's Lower Duffryn, at Cwmpennar near Mountain Ash, killed nineteen men and boys.
• Lower Duffryn Colliery explosion, 1860
  1860 · Explosion · 12 fatalities
  On 6 November 1860 an explosion in the Nine Feet vein of the Lower Duffryn Colliery, near Mountain Ash, killed twelve men and boys. It was the third fatal explosion at the colliery in a few years.

What's uncertain

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

• NMRS says it was also called the Middle Pit, while Welsh Coal Mines has Middle Duffryn as a separate colliery. (disputed) ^1,2

Recorded claims

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

• Thomas Powell of the Gaer opened the Lower Duffryn, or Cwmpenner, colliery in the early 1850s; it had Upper (376 yards) and Lower (345 yards) shafts about 350 yards apart. ^1,2
• Powell Duffryn Steam Coal Co. became the owners in 1864. ^1,2
• The colliery was the scene of a bitter industrial dispute in 1910, over the removal of old-established customs, which spread to the rest of the Cynon Valley. ²
• It stopped working in 1927 and officially closed as a production unit in July 1932; it was used for pumping until the 1970s. ^1,2
• NMRS says it was also called the Middle Pit, while Welsh Coal Mines has Middle Duffryn as a separate colliery. (disputed) ^1,2

Photographs & further reading

Sources

1. (secondary) Lower Duffryn (Cwmpennar), near Mountain Ash — Welsh Coal Mines
2. (secondary) Lower Duffryn Colliery — Northern Mine Research Society

Record created: 21 September 2026 · Last researched: 21 September 2026