Trevarrack United

Overview

A small tin mine in the granite of Lelant parish, two miles from St Ives Road station, known locally as Wheal Thunder, opened in 1871 under a lease from the trustees of W. Praed with a 36-inch engine and a 62-fathom engine shaft, which by 1873 had found tin only in small quantities; Brown's Shaft and its engine house have vanished and an overgrown burrow marks the site.

History

Trevarrack United tin mine lay in the parish of Lelant, two miles from St Ives Road station, north-west of Beersheba farm; the local name for it was Wheal Thunder. It was opened in 1871 under a lease for 21 years granted by the trustees of the late W. Praed at a royalty of one eighteenth. Kelly's directory of 1873 describes it: the country granite, the dip three feet in the fathom, several known lodes and three cross-courses, the mine worked and drained by a steam engine of 36-inch cylinder, and the engine shaft 62 fathoms under surface. Tin had as yet been found only in small quantities. The company was on the cost-book system, with Christopher Stevens as purser, James Pope as manager and Thomas Pearce as agent.

Dines noted a shaft known as Brown's Shaft surrounded by granite debris, and the Ordnance Survey of 1877 shows an engine house nearby; both have since vanished, and only an overgrown burrow on the boundary between two fields marks the site. No records of output survive.

Geology

Several tin lodes and three cross-courses in the granite of Lelant, dipping three feet in the fathom.

Geological setting: Veins and Lodes (historical documentary reference)

Workings

An engine shaft 62 fathoms deep worked and drained by a 36-inch steam engine, and Brown's Shaft with its granite debris; an engine house shown on the 1877 survey.

Closure

Unknown; tin had been found only in small quantities by 1873 and no output is recorded.

What remains

Brown's Shaft and the engine house have vanished; an overgrown burrow on a field boundary marks the site.

An overgrown burrow on the boundary between two fields.

Redevelopment

None.

Recorded claims

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

• Trevarrack United, in Lelant parish two miles from St Ives Road station, was held under a 21-year lease from 1871 granted by the trustees of the late W. Praed at a royalty of one eighteenth. ¹
• The mine was opened in 1871 and worked and drained by a steam engine of 36-inch cylinder, the engine shaft being 62 fathoms under surface in 1873. ¹
• The country is granite, the dip three feet in the fathom, with several known lodes and three cross-courses; tin had been found only in small quantities by 1873. ¹
• In 1873 the purser was Christopher Stevens, the manager James Pope and the agent Thomas Pearce, on the cost-book system. ¹
• Wheal Thunder is the local name for Trevarrack Mine, a small tin mine north-west of Beersheba farm with a shaft known as Brown's Shaft. ²
• An engine house shown on the 1877 Ordnance Survey and Brown's Shaft have both vanished, and only an overgrown burrow on a field boundary marks the site; no output records survive. ²

Photographs & further reading

Sources

1. (secondary) Trevarrack Mine, Cornwall — Cornwall Calling
2. (secondary) Wheal Thunder, aka Trevarrack Mine (Buddlepit Mine Database) — Buddlepit

Record created: 18 October 2026 · Last researched: 21 October 2026