Chromite
Species
Uncommon · FeCr₂O₄
Iron chromium oxide and the only commercial ore of chromium. It settles as cumulate layers in layered ultramafic intrusions and forms pods in the mantle rocks of ophiolites. Essential for stainless steel.
Identity
Crystallography
- Crystal system
- Cubic
- Habits
- Massive, Granular, Octahedral
- Fracture
- Uneven
Physical properties
- Mohs hardness
- 5.5
- Density
- 4.79 g/cm³
- Luster
- Metallic, Submetallic
- Colors
- black, brownish black
- Streak
- brown
- Transparency
- Opaque
Geology
- Origins
- Igneous
- Host rocks
- Ultramafic rock (peridotite, serpentinite)
- Associated minerals
- Olivine, pyroxene, Serpentine, Magnetite
- Found in
- Peridotite, Placer deposit
- Geography
- Kazakhstan, South Africa, India, Zimbabwe, Finland
Classification
- Rarity
- Uncommon
- Gem quality
- No
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, Chromite. Mineral Data Publishing, Handbook of Mineralogy, 1997.
- R. F. Schulte, Chromium, Mineral Commodity Summaries 2026. U.S. Geological Survey, 2026.
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