Dolcoath Mine, Tuckingmill, Carn Brea area, Camborne - Redruth - St Day District, Cornwall, England, UK

Dolcoath Mine started work for copper during the 1720s and became one of the leading Cornish copper producers before the end of the 18th century. In 1778, when it had reached a depth of 160 fathoms, Parys Mine, Anglesey (commenced in 1772) flooded the market and caused a considerable drop of the copper prices, which forced many Cornish mines to close. Though, with improved methods of pumping and the decline of Parys Mine in 1792, Dolcoath Mine again came to the fore and in 1815 had become the most important mine in Cornwall. From 1850, however, the output of copper started to fall from over 1,000 tons annually to nothing in 1878. In 1850, at a depth of 210 fathoms, the mine had reached the tin zone and the output of black tin rose steadily to over 2,000 tons a year in 1884. This output was maintained for about ten years before it started to decline. In 1896, the yield had dropped to 1,160 tons and from 1912, it fell rapidly to only 400 tons in 1918. Nonetheless, throughout the whole period since 1870, Dolcoath Mine remained the largest tin producer in the west of England, and it was not until 1917 that it was surpassed in this respect by East Pool Mine.

Around 1898, the West Dolcoath Exploration Syndicate acquired Camborne Consols, Camborne Vean Mine, Cooks Kitchen Mine, Stray Park Mine, West Stray Park Mine, Wheal Harriett, parts of the North and South Roskear Mines and all of the mines of the Pendarves United group except for Tolcarne, South Tolcarne and Great Condurrow Mine. However, no further work was done on any of these properties, except for the development of New Roskear Shaft (see below).

In 1920, exploration of the bottom levels became unprofitable and Dolcoath Mine had to close. The company directed interest now to the Roskear Mine group to the north, large parts of which had been acquired around 1898. In 1929, New Roskear Shaft was sunk to explore the rich tin ground which was believed to exist below the copper zone of these mines. However, the project was a complete failure: rich tin deposits only exist close to the granite contact, which steeply plunges to the north. Deposits at a greater distance from the contact carry mainly copper and only small amounts of tin. Although the shaft was sunk to a depth of 2,000 feet, the granite contact was not reached and economic quantities of tin were not encountered.

The original sett of Dolcoath Mine lies south of the Camborne-Redruth road, which approximately corresponds to its northern boundary. Its southern boundary is marked by the road running ENE from Camborne Beacon and crossing the Red River southwest of Carn Arthen. Its eastern boundary is Great Crosscourse which more or less follows the course of the Red River; the western boundary is Stray Park Crosscourse, which trends roughly parallel to the former at a distance of about three quarters of a mile.

The lodes, from north to south, are North Entral Lode, Silver Lode, South Entral Lode, Martin's Lode, Main Lode, Harriett Lode, Richard's Lode, South Lode, Caunter Lode and Brea Lode. They are trending in northeastern directions, except for Caunter Lode which trends E-W and intersects all lodes from Main Lode to South Lode. It was worked from New Shaft and from Harriett Shaft, which are located just north of the railway line, opposite to the Stray Park workings. The most important lode and also the most productive in the west of England was Main Lode, on which most of the shafts are sunk. It can be traced eastwards through Cooks Kitchen, Tincroft and Carn Brea Mines, and westwards through Camborne Vean Mine beyond which it dies out. Several small branches split on its footwall side, among them Culvert Course, Rule's Lode and Valley Caunter Lode, which were rich in copper ores. Silver Lode, which was developed chiefly from Freeman's Shaft in the west of the sett, 300 yards east of Roskear Street, produced acanthite and ruby silver.

The total output of Dolcoath and its associated mines is estimated at 350,000 tons of copper ore grading at 6-7.5% Cu and over 80,000 tons of black tin. In addition, small amounts of zinc, cobalt, nickel, bismuth and silver ores, and considerable quantities of arsenopyrite and pyrite were produced.

References:
- Dines, H.G. (1956): The metalliferous mining region of south-west England. HMSO Publications (London), Vol. 1, pp. 306-311.
- Embrey, P.G., and Symes, R.F. (1987): Minerals of Cornwall and Devon, pp. 42-43.