Cuprite is a red to brown mineral with high copper content. Its crystals are transparent to translucent; the color is dark red to cochineal red, brown red, purple red, sometimes almost black. Cuprite is often associated with native copper, malachite, azurite, limonite and chalcocite. Cuprite is named in 1845 by Wilhelm Karl von Haidinger from the Latin CUPRUM - copper, in allusion to its composition. Haidinger renamed a previously known mineral that had been known by a wide variety of names.
Cuprite has been a major ore of copper and is still mined in many places around the world. Some of the most outstanding lustrous dark red octahedral Cuprite crystals and groupings come from Kolwezi, Katanga (Shaba), Democratic Republic of Congo. Exceptionally large crystals, often coated with a shiny green coating of Malachite, are well-known from Ogonja, Namibia; the classic locality for fine Cuprite is Tsumeb, Namibia. Other notable occurrences of cuprite include Ural and Altai Mountains, Russia; Arizona, USA; Dzezkazgan, Kazakhstan; Queensland, Australia; Cornwall, England; France, China, Chile and other localities.
Cuprite can form both as bright transparent red crystals, and as lustrous, submetallic to brilliant opaque crystals. Even the opaque form will have slightly red edges and slight transparency upon back-lighting. The "chalcotrichite" (from the Greek, meaning "hairy copper") variety typically shows greatly elongated capillary or needle like crystals forms.
Though almost all crystals of cuprite are far too small to yield faceted gemstones, one unique deposit from Onganja, South West Africa, which was discovered in the 1970s, has produced crystals which were both large and gem quality. According to Joel Arem, one-time curator for the Smithsonian National Gem and Mineral Collection in Washington DC, faceted cuprite of any size is considered one of the most collectible and spectacular gems in existence, with its deep garnet coloring and higher brilliance than a diamond. Only the gem soft nature prevents it from being among the most valuable jewelry stones.
