Tungsten

Tungsten, or wolfram, chemical element, symbol W; for physical constants see Periodic Table. Tungsten was discovered by brothers Fausto and Juan José de Elhuyar in 1783. It occurs in wolframite, scheelite, huebnerite, and ferberite. The element is prepared by reduction of the oxide with hydrogen or carbon. It is a steel-gray, hard, ductile, unreactive metal, and has the highest melting point and lowest vapor pressure of all metals. Alloys of tungsten have many high-temperature applications. Tungsten and its compounds are used in filaments for electric lamps and television tubes, fluorescent lighting, glass-to-metal seals, and high-speed tool steels.