Yelverton: grid reference SX471689

Notable minerals: Chalcopyrite.

Lady Bertha Mine is situated just over a mile northwest of Buckland Monachorum near Yelverton in West Devon. Lying just south of the sett of the Virtuous Lady copper mine, on the east bank of the River Tavy, opposite Tavy Consols. Indeed the arsenic ores were taken over to Tavy Consols for calcining. To the east lay Buller and Bertha sett. The mine worked from Moyle's Engine Shaft, Meadow Shaft and Eastern Shaft on a lode that is thought to be an eastern extension of the lode of Tavy Consols across the water.

Production records report that between 1855-67 and 1881-82 - 7,372 tons of 4.5% copper ore was raised along with 1,682 tons of arsenopyritein 1881-82. As Bertha Consols between 1888 and 1894 - 965 tons of copper ore. 1,714 tons of arsenic were produced between 1890 and 1899. For the period 1888 to 1893 - 5,173 tons of mispickel (arsenopyrite) were raised. 5 tons of black tin was produced between 1893-96.