Tyrolite

Tyrolite
Tyrolite
General
Category	Arsenate and carbonate minerals
Formula; (repeating unit)	CaCu5(AsO4)2CO3(OH)4·6H2O
IMA symbol	Tyl
Strunz classification	8.DM.10
Crystal system	Orthorhombic
Crystal class	Prismatic (2/m) ; (same H-M symbol)
Space group	P2/c (no. 13) or C2/c (no. 15)
Identification
Color	Blue to green
Crystal habit	Radial or botryoidal
Mohs scale hardness	1.5–2.0
Luster	Vitreous
Diaphaneity	Translucent
Specific gravity	3.1–3.2
Refractive index	nα = 1.694; nβ = 1.726; nγ = 1.730
References

Tyrolite is a hydrous calcium copper arsenate carbonate mineral with the formula Ca Cu₅(As O₄)₂CO₃(OH)₄⋅6H₂O. Tyrolite forms glassy, blue to green orthorhombic radial crystals and botryoidal masses. It has a Mohs hardness of 1.5–2.0 and a specific gravity of 3.1–3.2. It is translucent with refractive indices of nα = 1.694, nβ = 1.726, and nγ = 1.730.

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 specimen (4.0 cm × 2.6 cm × 2.6 cm (1.6 in × 1.0 in × 1.0 in)); from San Simon Mine in Santa Rosa-Huantajaya District, Iquique Province, Chile.
(Click image for details of the mineral chemistry.)

^ Warr, L. N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
^ Krivovichev, S. V. (1 August 2006). "Crystal chemistry and polytypism of tyrolite". American Mineralogist. 91 (8–9): 1378–1384. Bibcode:2006AmMin..91.1378K. doi:10.2138/am.2006.2040. S2CID 96895661.

[1] Warr, L. N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.

[2] Krivovichev, S. V. (1 August 2006). "Crystal chemistry and polytypism of tyrolite". American Mineralogist. 91 (8–9): 1378–1384. Bibcode:2006AmMin..91.1378K. doi:10.2138/am.2006.2040. S2CID 96895661.

[1]

[2]