Mashamba West Mine, Kolwezi District, Lualaba, DR Cong

Cu₂O

Crystal System: cubic
Colour: dark red to cochineal red, sometimes almost black.
Lustre: adamantine, sub-metallic, earthy
Habitus: octahedral, dodecahedral or rombododecahedral
Hardness: 3½ -4
Fracture: conchoidal
Cleavage: {111} and, rarely, on {001}.
Density:  6.15 g/cm³ 
Origin and geological occurrence: cuprite is commonly found as an oxidation product of native copper and sulfides in the upper zones of veins; often associated with malachite, azurite, limonite and chalcocite.

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Samples:

4.6 Cuprite Cuprite, microcrystalline deep red aggregate, coated by green malachite, surrounding a core formed by native copper. Capo Calamita, Elba Island, Tuscany, Italy. #oxides