Tyrolite
Formula: Ca2Cu9(AsO4)4(CO3)(OH)8 · 11H2O
Species: Arsenates Carbonates
Colour: Turquoise-blue, blue-green; light bluish green in transmitted light.
Lustre: Vitreous, Silky, Pearly
Hardness: 1½ – 2
Specific Gravity: 3 – 3.2
Crystal System: Monoclinic
Name: Named after its discovery locality, Falkenstein near Schwaz, Tyrol, Austria.
Type Locality: Falkenstein, Falkenstein mining district, Schwaz District, Tyrol, Austria
A secondary mineral found in the oxidized zones of copper deposits.
Note: Not all “tyrolites” may contain CO3 groups (see also Church, 1895) and some may be identical with the closely related tangdanite (the ideal formula of which contains no carbonate but sulphate instead). Tyrolite may also be confused with theisite and claraite.