Excellent intergrown crystals of pseudohexagonal Polybasite, an uncommon silver sulphosalt. The Polybasite is a typical silvery lead-grey with a metallic lustre, displaying abundant twinning and occurring with a development of white to colourless botryoidal Fluorite on the reverse side of the Polybasite crystals. Tiny crystals of brassy Chalcopyrite and Pyrite are scattered over the Polybasite. This is a top-grade museum specimen of the silver sulphosalt Polybasite from the Arizpe area in Sonora, Mexico.
Comments