Bournonite

BOURNONITE (from the name of the French mineralogist J. L. Bournon * EN: bournonite; DE: Bournonit; FR: bournonite; ES: bournonita; RU: бурнонит), the wheel ore, is the mineral of the class of the complex sulfides (sulfosalts), CuPbSbS3. The content is: Pb is 42.5%, Cu is 13%, Sb is 24.7%, S is 19.8%; there are often found the admixtures of Fe, Ag, Zn, Mn, Ni, Bi, As. Bournonite crystallizes itself into the rhombic crystal systems. The structure is of the chain-belt type. It forms the granular aggregates, and the individual grains among the other sulphides, it may be also found in the form of the tabular and short-prismatic crystals. There are characteristic the twins along the (110) plane, and the quadruplets in the shape of the cross. There have been noted the epitaxial intergrowths with galena. The colour is from steel-gray to lead-gray, the lustre is metallic, the cleavage is imperfect along the (010) plane. Bournonite is brittle. The density is 5700-5900 kilograms per cubic metre. The hardness is 3.0-3.5. Bournonite is opaque. Bournonite is dielectric.

Bournonite is the hydrothermal mineral, bournonite may be observed within the association with the fahlore ores, galena, pyrite, chalcopyrite, sphalerite, jamesonite, and boulangerite. During the weathering of bournonite, there form themselves: cerussite, malachite, and antimony ochres. The deposits are known within the USSR (Central Asia, Transbaikalia), and abroad, within Australia, countries of the South America (Chile, Peru, Bolivia), within Czechoslovakia, West Germany, and East Germany. In case of the significant concentrations, bournonite is the ore with lead, copper, and antimony. During the beneficiation, bournonite is extracted along the way with the sulfides of copper, lead, and antimony, with the usage of xanthates as the collectors.