Dolomite
Species
Common · CaMg(CO₃)₂
Calcium magnesium carbonate forming by replacement of limestone through magnesium-rich fluids. The process, called dolomitisation, is not fully understood. Reacts more slowly with acid than calcite, a useful field distinction.
Identity
- Formula
- CaMg(CO₃)₂
- Chemical class
- Carbonate
- Also known as
- Bitter spar, Pearl spar
- Ore of
- Magnesium
Crystallography
- Crystal system
- Trigonal
- Habits
- Rhombohedral, Massive, Granular
- Fracture
- Subconchoidal
Physical properties
- Mohs hardness
- 3.5
- Density
- 2.85 g/cm³
- Luster
- Vitreous, Pearly
- Colors
- white, gray, pink, yellow, brown
- Streak
- white
- Transparency
- Transparent, Translucent
Geology
- Origins
- Sedimentary, Hydrothermal
- Host rocks
- Limestone and chalk, Salt beds
- Associated minerals
- Calcite, Quartz, Pyrite, Barite
- Found in
- Dolostone, Limestone, Marble, Evaporite deposit
- Geography
- worldwide
Classification
- Rarity
- Common
- 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.
- Dolomite. Mindat.org (Hudson Institute of Mineralogy).
- J. W. Anthony, R. A. Bideaux, K. W. Bladh, M. C. Nichols, Dolomite. Mineral Data Publishing, Handbook of Mineralogy, 2001.
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