Class : Oxides and hydroxides
    Subclass : Oxides
    Crystal system : Cubic
    Chemistry : Cu₂O
    Rarity : Uncommon

Cuprite is a relatively uncommon oxide in the surface areas of copper deposits, where it generally coexists with native copper as well as other oxidized copper minerals such as malachite, azurite or chrysocolla. It was first described by the Austrian mineralogist, geologist and physicist Wilhelm Karl Ritter von Haidinger in 1845. Its name comes from the Latin cuprum (copper). The cuprite is blood red and translucent in small crystals while the larger crystals are often opaque, dark red to metallic black. Malachite pseudomorphs are common, azurite pseudomorphs are rarer. Generally massive and earthy, the developed crystals are rare, the most widespread form is the octahedron, but it can also crystallize in dodecahedra or cubes, note that there is an acicular variety by elongation according to [001] that we call "chalcotrichite". Cuprite is locally an important industrial mineral. It can also be cut in cabochon for jewelry, but its low hardness makes it useless.

In France, the Chessy copper deposit in the Rhône department is worldwide known for its magnificent octahedra and dodecahedra of malachite pseudomorph after cuprite, which can sometimes exceed 3 cm in size.

Many other French localities have produced micro-crystals like : Le Moulinal (picture on left), Le Crozet (Loire), Les Mas Dieu (Gard), Villecun (Hérault), Laguépie, Le Burc, Montroc (Tarn), Cap Garonne (Var), etc...

Penetration twins are common.

Malachite pseudomorphs are common (photo on left), cuprite crystals can also be replaced more rarely by azurite, these transformations come from a carbonation that follows the oxidation of Cu⁺ ions in Cu²⁺. Native copper pseudomorphs after cuprite crystals has been discovered, but also cuprite epitaxies on native copper crystals.

No fakes known.