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Element History – Brief Review

Tungsten is a heavy metallic element, a member of the third series of transition metals. It has the symbol W, its atomic number is 74, and its atomic weight is 183.85. The name is derived from the Swedish tung sten, meaning “heavy stone.” Tungsten is also known as wolfram, from WOLFRAMITE, the mineral from which the element was first recognized by the English chemist Peter Woulfe in 1779. The metal was first isolated in 1783 by Spanish scientists Jose and Fausto d’Elhuyar through the reduction, by means of charcoal, of the tungstic acid found in wolframite.

Tungsten occurs principally in the minerals scheelite, wolframite, huebnerite, and ferberite. In the United States these minerals occur most notably in California and Colorado. Elsewhere they are found in China, the Buryat republic of Russia, Kazakhstan, South Korea, Bolivia, and Portugal. The metal is obtained commercially by the reduction of tungstic oxide with hydrogen or carbon. The pure metal is steel gray to tin white in color. Its physical properties include the highest melting point of all metals, 3,410 deg C (6,170 deg F), a boiling point of 5,660 deg C (10,220 deg F), and a density of 19.3 g/cu cm.

Pure tungsten metal is easily forged, spun, drawn, and extruded, whereas in an impure state it is brittle and can be fabricated only with difficulty. Tungsten oxidizes in air, especially at higher temperatures, but it is resistant to corrosion and is only slightly attacked by most mineral acids. In keeping with the other Transition Elements, it displays a range of oxidation states: 0, +1, +2, +3, +4, +5, and +6. This accounts for the many complex ions and coordination complexes in which tungsten can be found. Tungsten is not known to have any biological significance.