These carrollite crystals are from Kamoya, in the Kambove District, Katanga Copper Cresent, Katanga, D.R. Congo. There are six commercial mines in this area and they contain fifteen different minerals including carrollite. It is a sulfide and a cobalt ore, containing the elements Cu, Co, S. This specimen consists of a crystalline calcite matrix that hosts several carrollite crystals. They have a bright silver color and a mirror, metallic, luster. This piece measures 1 1/2 x 1 3/4 x 1 3/8 inches or 38 x 41 x 35 mm. The largest crystal is 7 mm across.