Cabalzarite
Cabalzarite | |
---|---|
General | |
Category | Arsenate minerals |
Formula (repeating unit) | Ca(Mg,Al,Fe3+)2[AsO4]2·2(H2O,OH) |
Strunz classification | 08.CG.15 |
Crystal symmetry |
Monoclinic prismatic H-M symbol: (2/m) Space group: C 2/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 |
Crystal system | Monoclinic |
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
- ↑ 1.0 1.1 Cabalzarite mineral data from Webmineral
- ↑ 2.0 2.1 2.2 Cabalzarite mineral information on Mindat.org
- ↑ 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;