Heterogenite
Species
Uncommon · Co³⁺O(OH)
Cobalt oxyhydroxide, black to reddish brown, earthy, reniform or botryoidal, formed by weathering of cobalt sulfides such as carrollite. The most abundant oxidised cobalt mineral of the Katanga Copperbelt, which holds about 70 per cent of all that is known, and an important cobalt ore there, at some 64 per cent cobalt; it also lies in the soils above the ultramafic rocks of New Caledonia.
Identity
- Formula
- Co³⁺O(OH)
- Chemical class
- Oxide
- Ore of
- Cobalt
Crystallography
- Crystal system
- Hexagonal
- Habits
- Botryoidal, Stalactitic, Earthy, Massive
- Fracture
- Conchoidal
Physical properties
- Mohs hardness
- 4
- Density
- 4.3 g/cm³
- Luster
- Dull, Vitreous
- Colors
- black, brownish black, reddish brown
- Streak
- dark brown
- Transparency
- Opaque
Geology
- Origins
- Sedimentary
- Host rocks
- Ultramafic rock (peridotite, serpentinite)
- Associated minerals
- Malachite, Cuprite, Calcite
- Found in
- Lateritic deposit, Oxidized zone (gossan)
- Geography
- DR Congo (Katanga Copperbelt: Lubumbashi, Shinkolobwe), Germany (Schneeberg), Namibia (Tsumeb), Morocco (Bou Azzer), New Caledonia
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, Heterogenite. Mineral Data Publishing, Handbook of Mineralogy, 2001.
- Heterogenite. Wikipedia.
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