Article · Wikipedia archive · Last revised Jul 23, 2026

Haidingerite

Haidingerite is a calcium arsenate mineral with formula Ca(AsO3OH)·H2O. It crystallizes in the orthorhombic crystal system as short prismatic to equant crystals. It typically occurs as scaly, botryoidal or fibrous coatings. It is soft, Mohs hardness of 2 to 2.5, and has a specific gravity of 2.95. It has refractive indices of nα = 1.590, nβ = 1.602 and nγ = 1.638.

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Haidingerite
White crystals of haidingerite associated with yellow orpiment and red realgar from the White Caps Mine, Manhattan District, Nevada, United States.
General
CategoryMinerals
FormulaCa(AsO3OH)·H2O
Identification
Mohs scale hardness2 – 2.5
Specific gravity2.95

Haidingerite is a calcium arsenate mineral with formula Ca(AsO3OH)·H2O. It crystallizes in the orthorhombic crystal system as short prismatic to equant crystals. It typically occurs as scaly, botryoidal or fibrous coatings.1 It is soft, Mohs hardness of 2 to 2.5, and has a specific gravity of 2.95. It has refractive indices of nα = 1.590, nβ = 1.602 and nγ = 1.638.2

It was originally discovered in 1827 in Jáchymov, Czech Republic. It was named to honor Austrian mineralogist Wilhelm Karl Ritter von Haidinger (1795–1871).3 It occurs as a dehydration product of pharmacolite in the Getchell Mine, Nevada.1

See also

See also

References

References

  1. http://rruff.geo.arizona.edu/doclib/hom/haidingerite.pdf Mineral Data Publishing, Handbook of Mineralogy
  2. http://www.mindat.org/min-1797.html Mindat with location data
  3. http://www.webmineral.com/data/Haidingerite.shtml Webmineral data
  • Palache, C., H. Berman, and C. Frondel (1951) Dana’s system of mineralogy, (7th edition), v. II, pp.708–709.