Cabalzarite

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Cabalzarite
General
Category Arsenate minerals
Formula
(repeating unit)
Ca(Mg,Al,Fe3+)2[AsO4]2·2(H2O,OH)
Strunz classification 8.CG.15
Crystal system Monoclinic
Crystal class Prismatic (2/m)
(same H-M symbol)
Space group C2/m
Unit cell a = 8.925 Å,
b = 6.143 Å,
c = 7.352 Å,
β = 115.25°; Z = 2
Identification
Color Light brown, brownish pink, orange brown
Crystal habit Aggregates and clusters, granular
Fracture Irregular
Mohs scale hardness 5
Luster Vitreous
Streak White
Diaphaneity transparent
Specific gravity 3.89
Optical properties Biaxial
Refractive index nα = 1.700 nγ = 1.760
Birefringence δ = 0.060
References [1][2][3]

Cabalzarite is a rare arsenate mineral with formula: (Ca(Mg,Al,Fe3+)2[AsO4]2·2(H2O,OH). It is a member of the tsumcorite group. It crystallizes in the monoclinic system and typically occurs as clusters of crystals or granular aggregates.[1][2]

It was first described for samples from an abandoned manganese mine in Falotta, Graubünden, Switzerland and named for Swiss amateur mineralogist Walter Cabalzar. It was approved as a new mineral by the IMA in 1997. It has also been reported from the Aghbar mine in Ouarzazate Province, Morocco.[2]

References[edit]

  1. ^ a b Cabalzarite mineral data from Webmineral
  2. ^ a b c Cabalzarite mineral information on Mindat.org
  3. ^ Brugger J., Meisser N., Schenk K., Berlepsch P., Bonin M., Armbruster T., Nyfeler D. and Schmidt S. 2000: Description and crystal structure of cabalzarite Ca(Mg,Fe,Al)2(AsO4)2(H2O,OH)2, a new mineral from the tsumcorite group. American Mineralogist, 85(9), 1307-1314; [1]