Altaite

ALTAITE (named after the first discovery at the Altai * EN: altaite; DE: Altait; FR: altaite; ES: altaita; RU: алтаит) is the mineral of the tellurides class, Pb Te.

Altaite contains 60.2-61.3% of Pb, and 36.8-38.4% of Te; admixtures: Ag, Fe, Cu, S, Se. There are common the thin intergrowths of the tellurides of gold and silver; it often occurs in the tight intergrowths with the native Au and Ag, galena. It crystallizes in the cubic crystal system. The crystal structure is coordinate. The crystals are rare, it sometimes forms the granular aggregates, is usually found in the form of the fine interspersed grains (in the galena). The colour is tin-white with the yellowish tinge; there is characteristic the bronze-yellow iridescence.

The hardness is 2.5-3. The density is 8200-8300 kilograms per cubic metre. It is fragile.

It is hydrothermal in origin; it is noted in the small quantities in the ores of the lead-zinc and gold-silver deposits. Along with other tellurides, it is the main source of the accompanying obtainment of the tellurium during the metallurgical processing of the polymetallic ores. It is beneficiated like the galena. See also the "Ores of the trace elements" article.