Tungsten, aswell accepted as wolfram, is a actinic aspect with the actinic attribute W and diminutive amount 74. The chat tungsten comes from the Swedish accent tung sten anon translatable to abundant stone, admitting it is frequently alleged volfram in Swedish.
A hard, attenuate metal beneath accepted altitude if uncombined, tungsten is begin by itself on Earth alone in actinic compounds. It was articular as a new aspect in 1781, and aboriginal abandoned as a metal in 1783. Its important ores cover wolframite and scheelite. The chargeless aspect is arresting for its robustness, abnormally the actuality that it has the accomplished melting point of all the non-alloyed metals and the additional accomplished of all the elements afterwards carbon. Aswell arresting is its top body of 19.3 times that of water, commensurable to that of uranium and gold, and abundant college (about 1.7 times) than that of lead. Tungsten with accessory amounts of algae is generally brittle and hard, authoritative it difficult to work. However, actual authentic tungsten, admitting still hard, is added ductile, and can be cut with a hard-steel hacksaw.
Tungsten is found in the minerals wolframite (iron-manganese tungstate, (Fe,Mn)WO4), scheelite (calcium tungstate, (CaWO4), ferberite (FeWO4) and hübnerite (MnWO4). China produced 51,000 tonnes of tungsten concentrate in 2009, which was 83% of the world output. In the prelude to WWII China's production of tungsten played a role as China could use this leverage to demand material assistance from the US government. Most of the remaining production originated from Russia (2,500 t), Canada (1,964 t), Bolivia (1,023 t), Austria (900 t), Portugal (900 t), Thailand (600 t), Brazil (500 t), Peru (500 t) and Rwanda (500 t). Tungsten is also considered to be a conflict mineral due to the unethical mining practices observed in the Democratic Republic of the Congo.
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