Mixite

Mixite
Mixite

Turquise-blue Mixite, Laurium, Greece. Size: 6.8 x 5.0 x 3.6 cm.
General
Category Arsenate minerals
Chemical formula BiCu6(AsO4)3(OH)6·3(H2O)
Strunz classification 08.DL.15
Identification
Crystal system Hexagonal


Mixite is a rare copper bismuth arsenate mineral with formula: BiCu6(AsO4)3(OH)6·3(H2O). It crystallizes in the hexagonal crystal system typically occurring as radiating acicular prisms and massive encrustations. The color varies from white to various shades of green and blue. It has a Mohs hardness of 3.5 to 4 and a specific gravity of 3.8. It has an uneven fracture and a brilliant to adamantine luster.

It occurs as a secondary mineral in the oxidised zones of copper deposits. Associated minerals include: bismutite, smaltite, native bismuth, atelestite, erythrite, malachite and barite.

It was discovered in 1879 near J´achymov, Czech Republic by mine engineer Anton Mixa.

References