Ironstone quarry where the Weardale Iron Company worked flats in the Great Limestone adjacent to Slitt Vein in the 1880s. The vein remains in a rib of less altered limestone up the centre of the quarry and the remains of earlier lead workings can be seen in the vein.
There was also a small fluorspar working ia a sahaft at the eastern end of the opencut in the 1950s.