Llwynhelig Colliery

Overview

A steam-coal drift at Cwmdare, west of Aberdare, started by the Llewellyns about 1906 in the thin Gorllwyn seam, an early user of electric coal-cutters, and abandoned in 1946.

History

Llwynhelig was driven west of Aberdare, at Cwmdare, by Rees Llewellyn and Sons about 1906 to work the Gorllwyn seam for steam coal; Welsh Coal Mines says it was first called Mechanical and renamed the following year. The Gorllwyn was only 18 inches thick, and by June 1909 it was being undercut by one of the first electric coal-cutters in the coalfield, its cutting bar 3 feet 9 inches long with 32 teeth.

The Llwynhelig Colliery Company was incorporated in January 1912 with £20,000 capital to take it over, and it passed to D. R. Llewellyn about 1915. It employed 164 in 1913, 225 in 1918 under Rees Davies and 250 in 1920, raising 50,000 tons; in 1923 it was producing about 65,000 tons a year, and Welsh Coal Mines puts its peak at 405 in 1925. G. B. Barling managed it from the late 1920s. The Gorllwyn Fach and Upper Graig were worked as well.

The Llwynhelig Drift abandoned the False Gorllwyn and Gorllwyn in 1931. Welsh Coal Mines has the colliery closing in 1932 and kept for drainage, taken over for that purpose by Powell Duffryn in 1938; NMRS and the abandonment plans date the final abandonment of the Gorllwyn and Gorllwyn Fach to 1946.

Geology

South Wales coalfield, Cynon valley: the Gorllwyn seam, about 18 inches, with the False Gorllwyn, Gorllwyn Fach and Upper Graig.

Workings

Drifts into the Gorllwyn, Old and New Llwynhelig, undercut by electric coal-cutters from 1909.

Closure

The drift abandoned the False Gorllwyn and Gorllwyn in 1931; Welsh Coal Mines says it closed in 1932 and was kept for drainage, under Powell Duffryn from 1938; the Gorllwyn and Gorllwyn Fach were abandoned in 1946.

What remains

Unknown.

Redevelopment

Unknown.

Related mines

• Dyllas Colliery — Both D. R. Llewellyn and Sons collieries.
• Windber Colliery — Neighbouring D. R. Llewellyn and Sons drifts at Cwmdare.

What's uncertain

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

• Employed 405 at its peak in 1925. (uncertain) ¹
• Closed in 1932 and kept for drainage, taken over by Powell Duffryn in 1938. (disputed) ¹
• Abandoned the Gorllwyn and Gorllwyn Fach seams in 1946. (disputed) ^2,3

Recorded claims

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

• Opened about 1905-06 by the Llewellyns to work the Gorllwyn seam for steam coal. ^1,2
• In June 1909 its 18-inch Gorllwyn seam was cut by one of the first electric coal-cutters in the coalfield. ²
• The Llwynhelig Colliery Company was incorporated on 15 January 1912 with £20,000 capital. ^1,2
• Employed 405 at its peak in 1925. (uncertain) ¹
• Closed in 1932 and kept for drainage, taken over by Powell Duffryn in 1938. (disputed) ¹
• Abandoned the Gorllwyn and Gorllwyn Fach seams in 1946. (disputed) ^2,3

Photographs & further reading

Sources

1. (secondary) Windber drift mine, Cwmdare; Llwynhelig; Dyllas — Welsh Coal Mines
2. (secondary) Llwynhelig Colliery — Northern Mine Research Society
3. (primary) BGS mine plans: Llwynhelig, Gorllwyn / Gorllwyn Fach, 1946 — British Geological Survey / Mining Remediation Authority
4. (primary) BGS mine plans: Llwynhelig Colliery, Upper Graig seam — British Geological Survey / Mining Remediation Authority

Record created: 7 October 2026 · Last researched: 7 October 2026