Tyrnyauz

a city (since 1955) under republic (ASSR) jurisdiction in the Kabarda-Balkar ASSR. Tyrnyauz is located on the upper course of the Baksan River, in the Terek River basin, 89 km southwest of Nal’chik. The city lies on the northern slope of the Greater Caucasus Mountains at an elevation of 1,300 m. Population, 20,000 (1975). Tyrnyauz was founded in the 1930’s in connection with the construction of a mining and metallurgy combine that uses tungsten-molybdenum ores. Tyrnyauz has plants that produce low-voltage equipment and reinforced-concrete products.

a tungsten-molybdenum deposit in the valley of the Baksan River, in the Kabarda-Balkar ASSR. It is associated with a complex of granitoids that formed in the Mesozoic and Cenozoic eras (during a period of tectonic-magmatic activity on the periphery of the Scythian Plate) and intruded into carbonaceous, terrigenous, and volcanogenic rocks of the Devonian, Carboniferous, and Jurassic periods. The principal mass of ore-bearing skarns is confined to the contact zone of hornfelses and marbles; the skarns, repeating the folded structure, form a great swell in the contact zone’s crest.

The molybdenum-tungsten ore bodies are concentrated in the skarns; the molybdenum ore bodies, in the biotitized hornfelses; and the tungsten ore bodies, in the skarnized marbles. The main ore minerals are scheelite with an admixture of Mo⁶⁺ (molybdo-scheelite), molybdenite, magnetite, pyrite, pyrrhotite, marcasite, arsenopyrite, chalcopyrite, sphalerite, tetrahedrite, tennantite, stannite, polybasite, and native silver and gold. The main gangue minerals are quartz, carbonates, fluorite, opal, and chalcedony. The mineral deposit measures more than 1 km vertically, and the tungsten content increases with depth. Some gold, arsenic, antimony, copper, lead, zinc, and silver is also encountered.

The deposit was discovered by B. V. Orlov in 1934. It has been mined since 1940 by the Tyrnyauz Mining and Metallurgical Combine; about 30 percent of the total output is produced by underground-mining methods, and about 70 percent by open-pit methods.