Frank Mills Mine

Overview

Frank Mills, in the Teign Valley south of Christow, was the most successful of Devon's silver-lead mines — deeper and more heavily worked than any of its neighbours, and productive enough that a boom in metal prices kept it going through the 1870s even as its ore grew steadily poorer.

History

Work at Frank Mills began around 1847, in an attempt to trace the northern extension of the same great lead lode already being worked further south in the district. Full-scale production followed from 1854, worked from Engine Shaft on both the West Lode and East Lode, and continued until 1880. Between 1857 and 1880 the mine raised 14,813 tons of 66% lead ore along with 248,530 ounces of silver — production that made Frank Mills easily the most successful, deepest and most exposed of the Teign Valley's silver-lead mines. The mine also raised significant quantities of other minerals as by-products: 873 tons of barytes in 1876-77 alone, 422 tons of iron ore between 1872 and 1880, and 176 tons of fluorspar in 1880. Mine manager J.P. Nicholls ran the operation through much of its middle years, from around 1857-58 to 1868, and an unusually high run of metal prices during the trade boom of the early 1870s helped keep the mine working longer than its increasingly poor-quality ore alone would otherwise have justified. The catastrophic and prolonged collapse in lead prices that began in 1878 and lasted into the mid-1890s finally forced Frank Mills to close in 1880, bringing the whole Teign Valley's silver-lead mining industry to an end with it.

Geology

The mine worked the West Lode and East Lode of a silver-lead vein system within the Teign Valley mining district on the eastern fringe of Dartmoor, part of the same hydrothermal, granite-related mineralisation as Dartmoor's tin lodes.

Geological setting: Hydrothermal Deposits (well documented example), Veins and Lodes (well documented example)

Workings

The mine was worked from Engine Shaft on both the West Lode and East Lode; a tapering ventilation shaft, now a listed structure, survives roughly 400 metres north-west of Little Hyner alongside a ruinous engine house building.

Closure

The mine closed in 1880 as the prolonged collapse in lead prices from 1878 finally made continued working uneconomic, ending silver-lead mining in the Teign Valley altogether.

What remains

Frank Mills and its neighbour Wheal Exmouth are, by size, among the more easily found abandoned mine remains in the Teign Valley; most of the district's other, smaller workings have been levelled, filled or reclaimed by agriculture and woodland.

An engine house and ivy-covered chimney survive near Hyner Farm, alongside a separately listed ventilation shaft near Little Hyner; the surrounding spoil heaps remain so heavily contaminated with lead and arsenic that they still support no plant cover today.

Recorded claims

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

• Between 1857 and 1880 the mine raised 14,813 tons of 66% lead ore and 248,530 ounces of silver, making it the most successful of the Teign Valley's silver-lead mines; it also produced 873 tons of barytes in 1876-77, 422 tons of iron ore between 1872 and 1880, and 176 tons of fluorspar in 1880. ^1,2
• The mine's surrounding spoil heaps remain so contaminated with lead and arsenic that they support no plant cover today. ²
• Frank Mills shared management with the neighbouring Wheal Exmouth and South Exmouth mines: J.O. Harris served as purser across all three from 1867-80, and J.P. Nicholls as mine captain from 1857/58 to 1868 — Frank Mills itself developed the southern extension of Wheal Exmouth's own lodes. ¹
• Silver sales at times contributed as much as 30 percent of Frank Mills' entire revenue, a reflection of how central the by-product had become to the mine's profitability as its lead ore grew poorer. ¹

Sources

1. (primary) The Teign Valley Silver-Lead Mines 1806-1880 — Northern Mine Research Society
2. (secondary) Frank Mills Mine (Frankmills Mine), Christow, Teignbridge, Devon, England, UK — Mindat
3. (primary) Frank Mills mine plans (BGS Mine Plans Catalogue) — British Geological Survey / The Coal Authority
4. (primary) Ventilation shaft and remains of building about 400 metres north-west of Little Hyner, Christow — Historic England (Listed Building record, via British Listed Buildings)

Record created: 22 August 2026 · Last researched: 28 August 2026