Cuprite — Cuprite
Cuprite Masha Milshina, Wikimedia Commons, CC BY 4.0

Mineral · Oxides

Cuprite

Cu2O

Cuprite is red copper oxide, forming octahedral and cubic crystals at Tsumeb, Chessy, Bisbee and Mashamba West (Congo), and hair-like chalcotrichite at Ray, Arizona. Deep red transparent Tsumeb and Congo cuprite octahedra are highly valued; the surface often dulls with a coating of malachite. Faceted cuprite is a collector's gem too soft for wear.

FormulaCu2O
IMA statusgrandfathered
Crystal systemCubic
Mohs hardness3.5–4
GroupOxides
Type localityNone
StreakBrownish red
Specific gravity6.1
Reference listIMA List of Minerals (RRUFF) — verify formula and status against the current list

Elsewhere

Cite this article

Stratum Strata. "Cuprite" (Mineral). Stratum Strata pack 2026.09, as of 2026-09-21. https://stratum.black/strata/minerals/cuprite. Accessed 2026-09-21.

@misc{stratum-cuprite,
  title        = {Cuprite},
  author       = {{Stratum Strata}},
  howpublished = {\url{https://stratum.black/strata/minerals/cuprite}},
  year         = {2026},
  note         = {Mineral article, Stratum Strata pack 2026.09, as of 2026-09-21; sources: stratum, wikidata, commons. Accessed 2026-09-21.}
}

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