Llwyndu Copper Mine

Overview

A short-lived copper mine near the summit between Grib Ddu and Bwlch y Sygyn above Beddgelert, briefly more successful than Sygun and Cwm Bychan; abandoned by 1844 and never reopened, it keeps an unusually complete set of dressing remains.

History

Llwyndu, also called Cribddu or Black Bush Mine, is a copper mine near the summit between Grib Ddu and Bwlch y Sygyn, above Beddgelert, between the Sygun and Cwm Bychan mines. According to David Bick, the Sygun works in Nant Gwynant had proved disappointing, and attention turned to Llwyndu with encouraging results; for a short period it did better than either Sygun or Cwm Bychan. It was working before 1841, when a quarter share in 'Llwyndu or Black Bush Mine' was offered at auction in London, and 38 tons of its ore had been sold in 1840. A drawing by William Pascoe of about 1841 shows its dressing house.

Ore was raised through a shaft to a 20-fathom level by a horse whim, and twenty girls were employed breaking ore on a paved cobbing floor below the manager's house. The mine continued with some success for a few years, but by 1844 it was yielding very little ore and was abandoned; it was never reopened. In use for about nine years, it left a well-preserved group of buildings, floors and a long calcining flue.

Geology

Unknown.

Workings

A pair of high adits on the steep hillside (the 'Old Workings'), a lower adit level shown on an 1842 section, and a vertical shaft to the 20-fathom level, wound by a horse whim.

Closure

Abandoned by 1844, when it was yielding very little ore; never reopened.

What remains

The site is unusually well preserved. The adit level leads down to a flooded level, and the shaft is covered.

A manager's or foreman's house of three rooms, a paved circular cobbing floor, spoil heaps, sedimentation tanks, a stone-covered calcining flue 30 to 40 m long, a horse whim circle, a picking floor, the remains of a dressing house, and a separate dressing house of about 1841 at Llyndy.

Redevelopment

Open hill land within Eryri National Park.

Related mines

• Cwm Bychan Copper Mine — Neighbouring copper mines either side of Bwlch y Sygyn.
• Sygun Copper Mine — Neighbouring Beddgelert copper mines; Llwyndu was opened up after Sygun disappointed.

Recorded claims

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

• After the Sygun works proved disappointing, attention turned to Llwyndu, which for a short period was more successful than Sygun or Cwm Bychan. ¹
• In 1841 a quarter share in Llwyndu or Black Bush Mine was offered for sale by auction in London, and 38 tons of ore had been sold in 1840. ²
• By 1844 Llwyndu was yielding very little ore and was abandoned; it was never reopened. ^1,2
• Twenty girls were employed to break ore on the mine's cobbing floor. ¹
• A vertical shaft wound by a horse whim led to the 20-fathom level. ¹
• A drawing by William Pascoe of about 1841 labels a building at Llyndy, associated with the Llwyndu mine, as a dressing house. ³

Sources

1. (secondary) Llwyndu Copper Mine Processing Area (NPRN 411438) — Coflein (RCAHMW)
2. (secondary) Llwyndu (Buddlepit Mine Database) — Buddlepit Mine Database
3. (secondary) Dressing House, Llyndy (MNA132617) — National Trust Heritage Records

Record created: 19 October 2026 · Last researched: 19 October 2026