Fluorite, CaF2 , also called fluorspar is calcium fluoride. The specimen is from Smallcleugh mine, Alston moor, Cumbria, and seems to be the result of at least two episodes of deposition. The first deposit is one of very small, almost colourless cubic crystals, some of which are edged in deep purple ( see inset 12mm view ). The second deposition is not so widespread, and is an indistinct scab like deposit ,which takes on a pale purple hue in places. Minor sphalerite is also present on the specimen.