Tyrolite

Tyrolite is a hydrated calcium copper arsenate carbonate mineral with formula: CaCu5(AsO4)2CO3(OH)4·6H2O. Tyrolite forms glassy blue to green orthorhombic radial crystals and botryoidal masses. It has a Mohs hardness of 1.5 to 2 and a specific gravity of 3.1 to 3.2. It is translucent with refractive indices of nα=1.694 nβ=1.726 and nγ=1.730.

Tyrolite
General
CategoryArsenate minerals
Formula
(repeating unit)
CaCu5(AsO4)2CO3(OH)4·6H2O
Strunz classification8.DM.10
Crystal systemMonoclinic
Crystal classPrismatic (2/m)
(same H-M symbol)
Space groupP2/c (no. 13) or C2/c (no. 15)
Identification
References[1]

It is a secondary mineral formed by the weathering of associated copper and arsenic minerals. It was first described in 1845 for an occurrence in Schwaz, Tyrol, Austria.

Chrysocolla on Tyrolite and Clinotyrolite, San Simon Mine, Santa Rosa-Huantajaya District, Iquique Province, Chile. 4.0 x 2.6 x 2.6 cm. Click image for details of the mineral chemistry.

References

  1. Krivovichev, S. V. (1 August 2006). "Crystal chemistry and polytypism of tyrolite". American Mineralogist. 91 (8–9): 1378–1384. doi:10.2138/am.2006.2040.



This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.