Letcha Mine

Overview

A tin sett on the south side of the Cot Valley near St Just, adjoining Wheal Hermon to the east, worked with Hermon and Wheal Oak until 1835 and mapped by Symons in 1857 as Letcha Mine, with Hermon only its north-western corner. A ruined chimney stands on the plateau above Letcha cliff.

History

Letcha, from the late Cornish for a frying pan, lay on the south side of the Cot Valley, or Kelynack valley, near St Just, adjoining Wheal Hermon to the east, with Wheal Oak on the cliffs to the south. Hermon is the oldest Cornish mine to appear on a map, about 1560, and at one time it was worked together with Letcha and Oak. The three were worked together until 1835, when Hermon was offered for sale. The sett is also recorded as the Lecha tin bounds.

When Symons mapped the district in 1857 he named the whole sett Letcha Mine, showing Wheal Hermon as occupying only its north-western corner. The most productive lodes of the Hermon workings outcrop on a line running from just south of Pen Nanven to Letcha Farm, and most of the documented shafts lie along it. In the 1880s tin was streamed on the Letcha foreshore.

In 1924 Corderoy Mines Ltd acquired Hermon together with Letcha and Progo and granted an option to work to the Uroz Company, but the venture ended four years later without any production. The ground was surveyed for the National Trust's archaeological assessment of Letcha and the Cot Valley in 1996-97, and lies within the Cornwall and West Devon Mining Landscape World Heritage Site.

Geology

Tin lodes in the granite-margin country of the St Just district. The Hermon and Letcha ground carries at least seven lodes or groups of lodes, most trending north-west to south-east.

Workings

Outcrop workings and shafts on lodes running from Pen Nanven to Letcha Farm, and tin streaming on the Letcha foreshore in the 1880s.

Closure

Worked with Hermon and Oak until 1835; acquired with Hermon and Progo by Corderoy Mines Ltd in 1924, under an option that lapsed after four years without production.

What remains

A ruined engine-house chimney and walling stand on the plateau above Letcha cliff. Several shafts in the Hermon and Letcha ground were made safe with stone hedges, fencing and a grille in 1997.

A chimney stack and the ruined walls of an engine house; shafts and outcrop pits on the lodes towards Letcha Farm.

Redevelopment

Unknown.

Related mines

• Wheal Hermon — Adjoining setts worked together until 1835; Symons's 1857 Letcha Mine took in Hermon (kept as separate records under the user's ruling of 2026-10-08).

Recorded claims

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

• Letcha, late Cornish for a frying pan, adjoins Wheal Hermon to the east. ¹
• Wheal Hermon was worked with Letcha and Wheal Oak until 1835, when it was offered for sale. ^2,1
• In 1857 Symons named the sett Letcha Mine, with Wheal Hermon occupying only its north-western corner. ²
• In 1924 Corderoy Mines Ltd acquired Wheal Hermon together with Letcha and Progo. ²
• The sett is also recorded as the Lecha tin bounds. ³
• Letcha Foreshore Tin Stream Works appears in the official lists of mines for 1884-1888. ⁴
• A ruined tin-mine chimney stands on the plateau above Letcha cliff. ⁵

Photographs & further reading

Sources

1. (secondary) 1716 | Sale of Black Tin from Wheal Hermon, St Just to Angarrack Smelting House — Angarrack Life
2. (primary) Wheal Hermon Tin Mine, Letcha and the Cot Valley, St Just — National Trust Heritage Records
3. (secondary) Letcha Mine — Northern Mine Research Society
4. (secondary) Letcha Foreshore Tin Stream Works — Northern Mine Research Society
5. (observational) File:Letcha Mine Cornwall.jpg (photograph and description, 2007) — Wikimedia Commons

Record created: 30 September 2026 · Last researched: 8 October 2026