Cuprite is an oxide mineral composed of copper(I) oxide Cu2O, and is a minor ore of copper.[ variety typically shows greatly elongated (parallel to 001) capillary or needle like crystals forms.
It is a secondary mineral which forms in the oxidized zone of copper sulfide deposits. It frequently occurs in association with native copper, azurite, chrysocolla, malachite, tenorite and a variety of iron oxide minerals.][Hurlbut, Cornelius S.; Klein, Cornelis, 1985, Manual of Mineralogy, 20th ed., Wiley, p. 299-300 ] It is known as ruby copper due to its distinctive red color.
Cuprite was first described by Wilhelm Karl Ritter von Haidinger in 1845 and the name derives from the Latin cuprum for its copper content.[
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Cuprite is found in the Ural Mountains, Altai Mountains, and Sardinia, and in more isolated locations in Cornwall, France, Arizona, Chile, Bolivia, and Namibia.[Joel E. Arem, Ph.D., F.G.A., Color Encyclopedia of Gemstones, 1977, Van Nostrand Reinhold Company]
As a gemstone
Though almost all crystals of cuprite are far too small to yield faceted , one unique deposit from Onganja in Seeis, Namibia, which was discovered in the 1970s, has produced crystals which were both large and gem quality. Virtually every faceted stone over one carat (0.2 g) in weight is from this single deposit, which has long since been mined out. The number of faceted gems over two carats (0.4 g) is difficult to estimate, but according to Joel Arem, one-time curator for the Smithsonian National Gem and Mineral Collection in Washington, D.C., 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's soft nature prevents it from being among the most valuable jewelry stones.
See also
