Wheal Exmouth, Christow, Teign Valley, Dartmoor & Teign Valley District, Devon, England, UK

Ancient lead mine.
Ref.: PG Embrey, RF Symes: "Minerals of Cornwall and Devon", BMNH publications (1987)
The works of this mine sit along a north-south lode like those at Frankmills nearby.
The tips in the present day run from the engine house, which has now been restored as a house with the unusual octagonal chimney and a second with an ornate corbel, down a shallow valley and across the main road to the river bank (300 to 400m in total length). These tips are composed of crushed local slate in places stained with iron or yellow lead oxide. A public footpath (public swamp may be a better description) runs from top to bottom of the works.
The tip between the road and the river yields galena and barite in reasonable quantity and small soft samples of pyromorphite. There is also a very localised pocket of linarite in which it is very abundant but the area is amybe only 2m x 3m in a small gulley. The rest of the tips are almost barren except the big tip at the top end of the works which contains galena, arsenopyrite and sphalerite. The stream that runs from these higher tips has a green look, similar to that at Gawton (near Tavistock) or Wheal Emma (Buckfastleigh) which suggests a fairly high copper content though only one flake of secondary copper (malachite possibly) was observed and a small piece of linarite. A test on the water shows only trace copper but testing a clean, solid piece of galena gives a strong copper test (but no positive silver test).
A study on arsenic accumulation in wood mice was carried out at this site and found that the mice had 3 times the normal level of arsenic in their systems, in direct proportion to the elevated levels in the tips. However, in comparison to some other sites in Devon and Cornwall the occurance of arsenopyrite at Wh Exmouth is a rarity. Feb 2008.
The engine was the largest on the mines in the Teign Valley but the mine was worked out by 1875. It produced both lead (and silver) but also 1560 tones of zinc ore. In 1977 a proposal to rework the tips for metals was rejected.
Stafford Clark - Mining & Quarrying in the Teign Valley, Orchard Publications, Chudleigh 1995.
The mine expoited 2 lodes 15 fathoms apart but closer at depth. A section of the mine from 1872 shows 'Barytes Lode' below 42 fathoms. The tips include cherty quartz with galena, sphalerite and copper sulphides.
Dines H.G. 1956