Altaite

Altaite

COLOR

Pure white. In spite of its softness, takes a good polish.

REFLECTANCE

Quite high, almost the same as metals. Galena is much darker and by direct comparison with altaite, has a purplish brown-pink tint.

ANISOTROPISM

Isotropic

TEXTURE

Cleavage similar to galena which may cause triangular pits during polishing. They are however much rarer than in galena. Altaite is often fringed with a strongly anisotropic, brownish alteration crust of an unknown composition. The mineral is sometimes found as minute inclusions together with hessite, melonite and coloradoite in some chalcopyrite or bornite from volcano-sedimentary deposits.

ASSOCIATED MINERALS

All the tellurides, galena, chalcopyrite, native gold.

CRITERIA OF DETERMINATION

Veru high reflectance, pure white color, isotropism, softness and association with other tellurides are characteristic. The cleavage is similar to that of galena.

Source

ATLAS OF ORE MINERALS (P. Picot and Z. Johan)