Proustite (redirected from Ruby silver ore)

proustite [′prü‚sīt]

(mineralogy)

Ag₃AsS₃A cochineal-red mineral that crystallizes in the rhombohedral system, consists of silver arsenic sulfide, is isomorphous with pyrargyrite, and occurs massively and in crystals. Also known as light-red silver ore; light-ruby silver.

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Proustite 

(also light red silver ore), a mineral of chemical composition Ag₃AsS₃. It crystallizes in the trigonal system, and its basic structure consists of pyramidal groups of AsS₃ and spiral-shaped chains of Ag₂S. Proustite occurs as disseminated grains, crystals, and compact masses. It is ruby red in color and brittle, with a hardness of 2–2.5 on Mohs’ scale and a density of 5,570–5,670 kg/m³. It is formed chiefly in lead-zinc-silver hydrothermal ore deposits. Although it is one of the basic minerals in silver ore, it is less widespread than pyrargyrite and does not form significant accumulations.

In the USSR, there are deposits of proustite in the Altai, the Far East, Kazakhstan, and Middle Asia. The mineral is also found in the German Democratic Republic, the Federal Republic of Germany, Czechoslovakia, Canada, Mexico, Bolivia, Peru, and Chile. Methods have been developed for growing proustite crystals of optical quality from melts. Proustite is a ferroelectric and is transparent in the infrared region. It is considered a promising material for nonlinear optics and acousto-optical devices.

A. S. MARFUNIN