Braunite
Species
Uncommon · Mn²⁺Mn³⁺₆O₈(SiO₄)
A manganese silicate oxide, dark brownish black to steel grey, submetallic and hard, formed by metamorphism of manganese silicates and oxides. It is found in the Kalahari manganese field of South Africa, in the manganese districts of Nagpur and Madhya Pradesh in India and at Miguel Burnier in Brazil.
Identity
- Formula
- Mn²⁺Mn³⁺₆O₈(SiO₄)
- Chemical class
- Silicate
- Ore of
- Manganese
Crystallography
- Crystal system
- Tetragonal
- Habits
- Pyramidal, Granular, Massive
- Fracture
- Uneven
Physical properties
- Mohs hardness
- 6
- Density
- 4.8 g/cm³
- Luster
- Submetallic
- Colors
- brownish black, steel gray
- Streak
- brownish black to steel-gray
- Transparency
- Opaque
Geology
- Origins
- Metamorphic, Sedimentary
- Associated minerals
- Pyrolusite, Rhodonite, Spessartine, Hematite
- Geography
- South Africa (Kalahari manganese field, Kuruman), India (Nagpur, Maharashtra; Tirodi, Madhya Pradesh), Brazil (Miguel Burnier, Minas Gerais), Sweden (Långban), Germany (Ilfeld, Harz), Italy (Saint-Marcel, Aosta Valley)
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, Braunite. Mineral Data Publishing, Handbook of Mineralogy, 2001.
- Braunite. Wikipedia.
- Cannon, W.F., Kimball, B.E., Corathers, L.A., Manganese, chap. L of Critical Mineral Resources of the United States (Professional Paper 1802-L). USGS, 2017.
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