Estimated Grid Ref. Part of Grambler and St. Aubyn. Operated a set of mineral veins trending east-northeast, located to the south of the Redruth-St Day road. These veins were accessed through a sequence of shafts arranged in a line stretching from South Trefula to Trefula hamlets. The coordinates provided are for Engine shaft, situated in the eastern section of the mining area. Between 1859 and 1867, the mine yielded a total of 2,670 tons of copper ore with an average grade of 8%.