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cubic Oxides

Cuprite

Formula Cu2O

Crystal Structure

#! Species: Cuprite #! System: Cubic (m3m) #! Habit: Octahedron with cube truncation cubic[m3m]:{111}@1.0 + {100}@0.5
cubic
m3m
{111} {100}

Quick Facts

Hardness
3.5
Specific Gravity
6.0
Refractive Index
2.848
Optical Character
Isotropic

Physical Properties

Crystal System
cubic
Hardness (Mohs)
3.5
Specific Gravity
6.0
Cleavage
Imperfect {111}
Fracture
Conchoidal to uneven
Lustre
Adamantine to sub-metallic

Optical Properties

Refractive Index
2.848
Optical Character
Isotropic
Pleochroism
None (isotropic)

Characteristics

Colours
Deep redBrownish-redPurplish-redNearly black (dark crystals)
Localities
Namibia (Onganja - historic gem source)Arizona (USA - Bisbee, Morenci)AustraliaDemocratic Republic of CongoCornwall (England - historic)
Crystal Forms
octahedroncubedodecahedron

Notes

RI over refractometer limit; extremely high SG aids identification