Tungsten is an element, which is also called wolfram, its chemical symbol is W. The metall in pure form is steel gray and quite pliant and easily processed, but small amounts of oxygen or carbon increase its hardness and brittleness. It has several interesting features, like the highest melting point of all elements except carbon (3,422°C), an extremely high conductivity which is 28% greater than that of silver. Its main use is the manufacture of hardmetal, a steel alloy with tungsten monocarbide. It is used in lighting filaments, electronic contacts, wires and rods. The chemical industry uses tungsten as a catalyst.
The most important tungsten ores are wolframite (iron-manganese tungstate, (Fe,Mn)WO4) and scheelite (calcium tungstate, CaWO4). Scheelite was originally called tungstenite, but it was renamed scheelite in honour of Carl Wilhelm Scheele, who discovered in 1781 that a new acid, tungstic acid, could be made from it. He suggested that it might be possible to obtain a new metal by reducing this acid. Two years later the brothers José and Fausto Elhuyar produced tungstic acid from wolframite. Later that year they reduced it with charchoal and discovered wolfram.
Most wolfram is mined in China and the GUS, Austria and Portugal, but there is a huge mine in Canada which is called CanTung (Canadian Tungsten), even the nearby miners town is named Tungsten. The price of tungsten depends very much on the world market and changes massively, as a result the mines are often closed and reopened a few years later. It changed its price by the factor of 10 during only 10 years and finnaly reached record prices since 2005, so at the moment tungsten mining is a profitable thing.
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