Tungsten Ores

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Tungsten Ores

 

natural mineral formations containing tungsten in amounts that make their extraction economically feasible. The chief minerals of tungsten are wolframite, containing 74-76 percent WO3, and scheelite, containing 80 per-cent WO3. The minimum concentrations of tungsten trioxide at which it is profitable to work tungsten ores at the present level of economic and technological development (1960-70) are of the order of 0.14—0.15 percent for large deposits and 0.4-0.5 percent for smaller, vein deposits. Tungsten ores often contain other useful components (tin, molybdenum, beryllium, gold, copper, lead, and zinc). In addition, the wolframites of some deposits contain large amounts of tantalum and scandium, which can be extracted from them. To obtain concentrates containing 50-60 percent WO3, the ores are enriched using gravitational, flotation, and other methods of concentration.

Endogenic deposits of tungsten are postmagmatic, pneumatolytic, or hydrothermal and are genetically associated with granite intrusions. The following types of tungsten ore deposits are differentiated: albitized, greisened, and silicified cupolas and stocks of granites or granitized porphyry, containing finely disseminated wolframite and some-times thin quartz-wolframite veins and forming a stockwork; quartz-feldspar, quartz-topaz, quartz-fluorite, and quartz veins, often with greisen selvages containing wolframite and rarely scheelite, cassiterite, beryl, arsenopyrite, bismuthinite, molybdenite, pyrite, and other sulfides; quartz-scheelite veins, mineralized zones, and stock works, often containing sulfides; quartz-gold-scheelite and quartz-antimonitescheelite bodies containing ferberite, antimonite, cinnabar, and barite; and scheelite-containing scarns of garnetpyroxene-scapolite composition, containing molybdenite, chalcopyrite, galena, and sphalerite. The richest are deposits of the vein type, which often contain up to several percent WO3. The largest deposits are the skarn and stockwork types. Deluvial and alluvial placers containing wolframite and scheelite may form because of erosion of direct deposits.

There are large deposits of tungsten ores in the USSR (Transbaikalia, Middle Asia, Kazakhstan, Primor’e, and the Northeast), the People’s Republic of China, and the Korean Democratic People’s Republic. Capitalist countries prominent for their reserves and mining of tungsten ores (1966 output in tons of WO3) include the USA (4,852), Bolivia (1,580), Australia (1,326), Portugal (1,199), Peru (437), Thai-land (336), and Burma (207).

REFERENCES

Bybochkin, A. M. Mestorozhdeniia vol’frama i zakonomernosti ikh razmeshcheniia. Moscow, 1965.
Mineralogiia i geokhimiia vol’framovykh mestorozhdenii. [Leningrad] 1967.

A. I. GINZBURG

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
The tungsten ores were received from around the world and smelted to produce items such as tungsten carbide powder, tungsten wire, and welding rods.
Tungsten ores also occur as finely divided particles in a greisen-type stockwork.
The country also has copper, zinc, iron, and tungsten ores, as well as marble, sand and semi-precious rock reserves.
Small processing plants range in size from about 10-200 t/d of ore for batch or semi continuous manual or mechanical treatment, using a jig or a few tables, for gold, tin and tungsten ores for example, to continuous 24 h/d and 5-7 day per week operations: flotation plants of 50-200 t/d capacity, processing simple or complex sulphide base metal ores containing lead/copper and/or zinc, with some gold and silver values.
High price and demand for acceptable tungsten concentrate offer a very attractive incentive for the exploration of tungsten ores. China is the leading producer of tungsten concentrate.
The authors are highly grateful to The College of Earth and Environmental Sciences, University of the Punjab, Lahore for supplying about three tonnes of tungsten ore for the present study.
Processing of low-grade tungsten ore concentrates by hydrometallurgical route with particular reference to India.
Economically important tungsten ore deposits have been found at Mineki Gol and adjoining area, near Garam Chasma, about 60 km to the north of Chitral city, in Khyber Pakhtoonkhwa province of Pakistan.
The samples of tungsten ore were collected from various localities of Mineki Gol area.
The complete chemical analysis of the representative sample of ore and final concentrate is presented in Table 1, which indicates the presence of 0.34 % W[O.sub.3] content in the tungsten ore of Chitral area of Pakistan.