Lead and later fluorspar mine working Slitt Vein. First driven as a horse level by WB Lead Company in 1847 working ore in the Scar Limestone and originally called Cammock Isle. Later reworked as a fluorite mine. First produced fluorite in 1906, worked by various companies, Swiss Aluminium UK put in a decline which got down below the whin sill. Closed in the mid 1980's, the decline is flooded to the entrance and the horse level has collapsed where it reaches the vein