Today hamstone is quarried in only two areas of Ham Hill. The North quarry, run by Ham & Doulting Stone, extracts stone from just beneath the surface and is the longest running hamstone quarry in existence. The Norton or South quarry, run by Harvey Stone, extracts its stone from some 20-30 metres below the surface. This quarry was formed by the re-opening of workings that were abandoned in the 1930s. Hamstone House was built with the last significant supply of hamstone from the quarries before their closure. Both quarries are owned by the Duchy of Cornwall.