Discovery Information
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Who: Fausto and Juan Jose de Elhuyar |
When: 1783 |
Where: Spain |
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Name Origin
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Swedish: tungs ten (heavy stone): W symbol from its German name wolfram. |
"Tungsten" in different languages. |
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Sources
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Occurs in the minerals scheelite (CaWO4), wolframite [(Fe,Mn)WO4], ferberite (FeWO4) and huebnerite (MnWO4). China produces about 70% of the world's supply, but important deposits lie in Bolivia, USA (California, Colorado), Portugal, Russia as well as South Korea.
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Annual production is around 45 thousand tons. |
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Abundance
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Universe: 0.0005 ppm (by weight) |
Sun: 0.004 ppm (by weight) |
Carbonaceous meteorite: 0.12 ppm |
Earth's Crust: 1.1 ppm |
Seawater: 1.2 x 10-4 ppm
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Uses
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Tungsten is a metal with a wide range of uses, the largest of which is as tungsten carbide (W2C, WC), which is one the hardest substances in existence. Cemented carbides (also called hardmetals) are wear-resistant materials
used by the metalworking, mining, petroleum and construction industries. Tungsten is widely used in light bulb and vacuum
tube filaments, as well as electrodes, because it can be drawn into very thin metal wires that have a high melting point.
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When alloyed in small quantities with steel, it greatly increases its hardness. Used widely in the electronics industry. Made into filaments
for vacuum tubes and electric lights. Also used in contact points in cars, heat sinks, weights, counterweights, welding electrodes,
rocket nozzles and cutting tools. Combined with calcium or magnesium it makes phosphors.
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Composites are used as a substitute for lead in bullets and shot.
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Recently, Tungsten Carbide has been used in the fashioning of jewellery due to its hypoallergenic nature and the fact that
due to its extreme hardness it is not apt to lose its luster like other polished metals.
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History
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Tungsten (Swedish tung sten meaning "heavy stone"), even though the current name for the element in Swedish is wolfram (sometimes
spelled in Swedish as volfram), from the denomination volf rahm by Wallerius in 1747, translated from the description by Agricola
in 1546 as Lupi spuma, meaning "wolf's froth" after the way tin is eaten up like a wolf after sheep in the process of its
extraction.
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It was first hypothesized to exist by Peter Woulfe in 1779 who examined wolframite and concluded that it must contain a new
substance. In 1781 Karl Wilhelm Scheele ascertained that a new acid could be made from tungstenite. Scheele and Torbern Bergman suggested that it could be possible
to obtain a new metal by reducing tungstic acid. In 1783 Jose and Fausto Elhuyar found an acid in wolframite that was identical
to tungstic acid. In Spain later that year the brothers succeeded in isolating tungsten through reduction of this acid with charcoal. They are credited with the discovery of the element.
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In World War II, tungsten played an enormous role in background political dealings. Portugal, as the main European source
of the element, was put under pressure from both sides, because of its sources of wolframite ore. The resistance to high temperatures,
as well as the extreme strength of its alloys, made the metal into a very important raw material for the weaponry industry.
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Notes
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Some sources give the German chemist Karl Wilhelm Scheele as the first to isolate the metal, three years before the d'Elhuyar brothers, in 1780.
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The light bulb manufacturer OSRAM (founded in 1906 when three German companies; Auer-Gesellerschaft, AEG and Siemens and Halske
combined their lamp production facilities), derived its name from the elements of OSmium and wolfRAM - OSRAM.
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Hazards
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Tungsten dust is flammable and may act as a respiratory irritant. |