Smithsonite
Species
Uncommon · ZnCO₃
Zinc carbonate forming in the oxidised zones of zinc ore deposits. Occurs in a wide range of colours depending on trace impurities. Named after James Smithson, whose bequest founded the Smithsonian.
Identity
- Formula
- ZnCO₃
- Chemical class
- Carbonate
- Mineral group
- Calcite, Rhodochrosite, Siderite
- Also known as
- Zinc spar, Bonamite (trade name)
- Ore of
- Zinc
Crystallography
- Crystal system
- Trigonal
- Habits
- Rhombohedral, Botryoidal, Massive, Earthy
- Fracture
- Subconchoidal
Physical properties
- Mohs hardness
- 4.5
- Density
- 4.45 g/cm³
- Luster
- Vitreous, Pearly
- Colors
- white, gray, green, blue, pink, yellow
- Streak
- white
- Transparency
- Translucent, Opaque
Geology
- Origins
- Sedimentary
- Host rocks
- Limestone and chalk
- Associated minerals
- Hemimorphite, hydrozincite, Cerussite, aurichalcite
- Found in
- Oxidized zone (gossan)
- Geography
- USA, Greece, Namibia, Mexico, Zambia
Classification
- Rarity
- Uncommon
- Gem quality
- Yes
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, Smithsonite. Mineral Data Publishing, Handbook of Mineralogy, 2001.
- Smithsonite. Gemdat.org (Hudson Institute of Mineralogy).
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