Trevaunance Mine

Overview

An old and once highly profitable copper and tin mine above Trevaunance Cove at St Agnes, part of the Polberro Mines (St Agnes Consols) complex, worked through most of the 19th century.

History

Trevaunance Mine, also known as Wheal Trevaunance, was an old working said to have paid out £100,000 in dividends over its life, and formed part of the wider Polberro Mines (St Agnes Consols) group above Trevaunance Cove. It worked from 1843 to 1887, producing some 1,960 tons of copper and 550 tons of tin; by 1864 the mine was 60 fathoms deep to adit and employed twelve people, though very little further sinking took place below that level. The mine's fortunes were tied to the same cove whose harbour -- repeatedly built and destroyed by storms since the Tonkin family's first attempt in 1710 -- served St Agnes's wider mining district for exporting ore and importing coal and timber. J. H. Collins, writing in 1912, recorded that at one time it was worked together with Goonlaze Mine, under the names Trevaunance Consols and Trevaunance United. As Trevaunance Consols it sold 1,158 tons of copper ore for £3,625 in 1843 and 1844; as Wheal Trevaunance it sold 550 tons of black tin between 1861 and 1883 and a further 510 tons in 1886 and 1887. The twelve at work in 1864 had become thirty by 1870.

Geology

Copper and tin of the St Agnes district; the lodes are not named on the record. Cassiterite occurs on joint planes in the metamorphosed killas, a stockwork, and the mine was known for fluorite crystals of an unusual four-faced cube form; topaz is also found.

Workings

Worked to 60 fathoms (to adit) by 1864, employing around twelve people at that time; part of the wider Polberro Mines (St Agnes Consols) group of workings above the cove. A 50-inch engine pumped the mine and an enclosed beam engine wound from it. A pit north of Trevaunance Road, opposite the winding engine base, may be an old openwork.

Closure

Closed in 1887 after a working life recorded from 1843, by which point the mine had long since ceased sinking deeper.

What remains

The stack of the pumping engine house survives as a prominent feature of the site, with the truncated base of an enclosed beam winding engine visible a short distance to the east. The 50-inch pumping engine house itself was demolished in the 1930s after being declared dangerous. The cylinder bedstone of the winding engine remains among the scant ruins of its house. A pit that may be a former openwork lies north of Trevaunance Road with large dumps beside it. The remains are on private land.

The pumping engine house stack and the base of a beam winding engine. Also the winding engine's cylinder bedstone, a pit north of Trevaunance Road and dumps.

Related mines

• Polberro Mine — Merged at the end: Polberro closed in 1895 after a merger with Trevaunance Mine, and both belonged to the St Agnes Consols group that gave Polberro its alternative name.

Recorded claims

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

• Trevaunance Mine worked from 1843 to 1887, producing about 1,960 tons of copper and 550 tons of tin. ¹
• By 1864 the mine was 60 fathoms deep to adit and employed twelve people, with very little work carried out below that level. ^1,2
• Trevaunance Mine is said to have paid its adventurers £100,000 in dividends over its working life. ¹
• Worked at one time with Goonlaze Mine as Trevaunance Consols and Trevaunance United, it sold 1,158 tons of copper ore for £3,625 in 1843-44, 550 tons of black tin in 1861-83 and 510 tons in 1886-87. ³
• Thirty people were employed by 1870. ³
• The surviving stack served a 50-inch pumping engine house that was demolished in the 1930s after being declared dangerous; the cylinder stone of the enclosed whim engine house remains. ^4,3

Photographs & further reading

Sources

1. (secondary) Tywarnhayle Mine Cornwall (St Agnes area page) — Cornwall Calling
2. (secondary) Trevaunance Mine (Wheal Trevaunance) — Mindat
3. (secondary) Trevaunance Consols (aka Trevaunance United or Wheal Trevaunance) — Buddlepit Mine Database
4. (secondary) St Agnes Mining District — Cornish Mine Images

Record created: 31 August 2026 · Last researched: 5 October 2026