Perfect Cuprite Crystal
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Perfect Cuprite Crystal, From Tsumeb Mine, Tsumeb, Namibia |
Cuprite
Formula: Cu2O
System: Isometric
Colour: Dark red to cochineal ...
Lustre: Adamantine, Sub-Metallic, Earthy Hardness:3½ - 4
From Villecun, Olmet-et-Villecun, Hérault, Occitanie, France
Its dark crystals with red internal reflections are in the isometric system hexoctahedral class, appearing as cubic, octahedral, or dodecahedral forms, or in combinations. Penetration twins frequently occur.
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. It is known as ruby copper due to its distinctive red color.