Cuprite
Species
Uncommon · Cu₂O
Copper oxide from the weathered cap of copper deposits, where it grows deep red cubes and octahedra. Transparent crystals are cut for collectors, though they are far too soft to be worn.
Identity
- Formula
- Cu₂O
- Chemical class
- Oxide
- Also known as
- Ruby copper
- Ore of
- Copper
Crystallography
- Crystal system
- Cubic
- Habits
- Cubic, Octahedral, Massive
- Fracture
- Conchoidal
Physical properties
- Mohs hardness
- 4
- Density
- 6.1 g/cm³
- Luster
- Adamantine
- Colors
- brown red, purple red, red, black
- Streak
- brownish red
- Transparency
- Transparent, Translucent
Geology
- Origins
- Hydrothermal
- Associated minerals
- Copper, Malachite, Azurite, Chrysocolla
- Found in
- Oxidized zone (gossan)
- Geography
- Namibia, Russia, Australia
Classification
- Rarity
- Uncommon
- Gem quality
- Yes
Sources
- M. Pasero and others, IMA Commission on New Minerals, Nomenclature and Classification, The New IMA List of Minerals, updated September 2026. International Mineralogical Association (CNMNC), 2026.
- J. W. Anthony, R. A. Bideaux, K. W. Bladh, M. C. Nichols, Cuprite. Mineral Data Publishing, Handbook of Mineralogy, 2001.
- Cuprite. Gemdat.org (Hudson Institute of Mineralogy).
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