At the top of the cliff-slope there are the remains of one of the finest surviving arsenic-refining works in Britain with remarkable extant flues and a large double bayed labyrinth. The chimney stack dates from an earlier working (it was associated with a stamps engine). The tin-dressing floors that survive in the surrounding landscape show the evolution of mineral-processing technologies from small-scale eighteenth century earthworks to the conspicuous concrete remains dating from 1906.