Treskerby Mine

Overview

A copper mine, with minor tin, on the northern flank of Carn Marth near Redruth, already active by 1800 and amalgamated with the adjoining Wheal Chance in 1828 to form Treskerby and Chance United Mine. Two later working phases, from 1860 and again in the 1920s, followed the original abandonment. Its surviving Grade II listed calcining plant — an arsenic flue and stack — is the mine's principal visible remnant.

History

Treskerby Mine and its neighbour Wheal Chance were both working lodes in metamorphosed killas overlying the northern flank of the Carn Marth granite, already active by 1800. In 1828 the two setts amalgamated as Treskerby and Chance United Mine, with shafts and workings on both sides of the Redruth-Truro road; the combined mine was abandoned a few years after the amalgamation. From 1815 to 1832 the mine had produced 47,545 tons of around 9.5% copper ore, with the Treskerby section separately raising 9 tons of black tin over the same period. In 1860 the property was reopened and partially dewatered, and a further working phase from 1922 to 1927 produced 18,500 tons of around 9% copper ore. A separate account of the wider Gwennap mining district gives Treskerby's total output as around 32,000 tons of copper ore — notably lower than the sum of the two production figures above, a discrepancy not resolved by either source. Wolframite-bearing rock found in the mine's dumps prompted prospection works in 1938, but the source of the tungsten ore was never located.

Workings

Worked lodes in metamorphosed killas over the northern flank of the Carn Marth granite intrusion; the Treskerby sett adjoined Wheal Boys to the west, along the County Crosscourse, and Wheal Chance to the east, and once extended 900 yards south-east of Treskerby village, at one time also taking in the Park-an-Chy Mine. The BGS/Coal Authority mine plans catalogue holds twenty records for the mine, recording tin and copper ore and abandonment dates of 1818 and 1890 among its plans.

What remains

Mine dumps have largely been reclaimed under an active tree-planting scheme; chalcopyrite-pyrite-arsenopyrite bearing rock can still be found, along with pale green fluorite and white opal as rock-forming material, though minerals occur only as scanty grains. The stack at the end of the surviving arsenic flue remains in good condition, though the calciner itself is crumbling and the flue is being reclaimed by undergrowth.

A calcining plant — an arsenic flue and stack — survives at the mine and was Grade II listed by Historic England on 24 May 1993 (NHLE 1253199), grid reference SW7172143678.

Abandoned workings can be dangerous — unstable ground, uncapped shafts, flooding and bad air are common even where a site looks safe from the surface. This entry describes history and general location only; it is not an access guide.

Recorded claims

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

• Treskerby Mine amalgamated with the adjoining Wheal Chance in 1828 to form Treskerby and Chance United Mine; the combined mine was abandoned a few years afterward. ¹
• From 1815 to 1832 the mine produced 47,545 tons of around 9.5% copper ore, with the Treskerby section separately raising 9 tons of black tin over the same period. ¹
• A later working phase from 1922 to 1927 produced 18,500 tons of around 9% copper ore. ¹
• A separate account of the wider Gwennap mining district gives Treskerby's total output as around 32,000 tons of copper ore, notably lower than the sum of the two production figures recorded by Mindat for 1815-32 and 1922-27; the discrepancy is not resolved by either source. (disputed) ^2,1
• Wolframite-bearing rock found in the mine's dumps prompted prospection works in 1938, but the source of the tungsten ore was never located. ¹
• The mine's surviving calcining plant (an arsenic flue and stack) was Grade II listed by Historic England on 24 May 1993 (NHLE 1253199). ³
• The BGS/Coal Authority mine plans catalogue holds twenty records for Treskerby, recording tin and copper ore with abandonment dates of 1818 and 1890 among the plans. ⁴

Sources

1. (secondary) Treskerby and Chance United Mine (incl. Treskerby Mine; Wheal Chance) — Mindat.org
2. (secondary) Gwennap Mining District — Cornwall Calling
3. (primary) Calcining Plant at Treskerby Mine (NHLE 1253199) — Historic England National Heritage List (via Wikidata)
4. (primary) Treskerby mine plan records — British Geological Survey / Coal Authority mine plans catalogue

Record created: 26 August 2026 · Last researched: 26 August 2026