New Duffryn Colliery

Overview

The Rhymney Iron Company's pit at Rhymney, sunk in 1867 to 220 yards with the older Duffryn pit as its upcast. A fall of roof released gas that exploded in June 1883, killing six; the pit was idle in 1896, reopened in 1898 and closed in the 1920s.

History

New Duffryn Colliery was one of the Rhymney Iron Company's pits at Rhymney, on the border between Glamorgan and Monmouthshire. The company had sunk the Old Duffryn pit nearby in 1837 to work the Upper Four Feet seam; when New Duffryn was sunk in 1867, to a depth of 220 yards in the Rhas Las seam, the old pit became its upcast ventilation shaft, and water from the new colliery was used by the ironworks. Old Duffryn was closed in 1896, when it employed 388 men underground and 50 on the surface, and its shaft was filled in 1953.

The colliery was worked on the longwall method and had been free of firedamp for more than forty years when, on 25 June 1883, a heavy fall of roof released gas that was fired at the men's naked lights; six died and eight were injured (see Disasters, below).

The Inspector of Mines listed New Duffryn as abandoned in 1896, but it reopened in 1898 with 361 men. It employed 269 in 1908 and 492 in 1918, and in 1923, worked with the company's Mardy pit, the two employed 1,801 men in the Rhas Las, Clay, Yard, Red and Lower Four Feet seams. It closed in the 1920s; a photograph of the 1930s shows its disused winding engine house and wooden headgear standing on the Rhymney ironworks site.

Geology

South Wales Coalfield: the Rhas Las (Gloyn Coch), Clay, Yard, Red and Lower Four Feet seams.

Workings

One shaft of 220 yards, with the Old Duffryn pit of 1837 as its upcast; longwall working.

Closure

Listed as abandoned in 1896, reopened in 1898 and closed in the 1920s.

What remains

Unknown.

Redevelopment

Unknown.

Related mines

• Mardy Colliery — Rhymney Iron Company pits worked together; in 1923 New Duffryn and Mardy employed 1,801 men between them.
• Rhymney Merthyr Colliery — Rhymney Iron Company pits at Rhymney and Pontlottyn, a short way apart.

Disasters & major incidents

• New Duffryn Colliery explosion, 1883
  25 June 1883 · Explosion · 6 fatalities
  A heavy fall of roof at the Rhymney Iron Company's New Duffryn Colliery, Rhymney, released gas that was fired at the men's naked lights on 25 June 1883; six died, the youngest a 13-year-old collier, and eight were injured.

Recorded claims

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

• Sunk by the Rhymney Iron and Coal Company in 1867 to 220 yards, with the Old Duffryn pit as its ventilation shaft. ¹
• Reopened in 1898 with 361 men; 269 were employed in 1908 and 492 in 1918. ¹
• In the 1930s its disused winding engine house and wooden headgear stood on the Rhymney ironworks site. ²

Sources

1. (secondary) New Duffryn colliery, Rhymney — Welsh Coal Mines
2. (secondary) New Duffryn Colliery, photograph (2015.99/5) — Amgueddfa Cymru - Museum Wales
3. (secondary) New Duffryn Colliery Explosion - Rhymney - 1883 — Northern Mine Research Society

Record created: 17 October 2026 · Last researched: 17 October 2026