Tungsten General Electric's attempt to patent it, overturning granted in 1913 to William D. Coolidge. Tungsten Tungsten, or wolfram, is a chemical element with symbol W and atomic number 74. The name "tungsten" comes from the former Swedish name for the tungstate mineral "scheelite", "tung sten" or "heavy stone". Tungsten is a rare metal found naturally on Earth almost exclusively combined with other elements in chemical compounds rather than alone. It was identified as a new element in 1781 and first isolated as a metal in 1783. Its important ores include wolframite and scheelite. The free element is remarkable for its
Melting point a liquid phase only exists above pressures of and estimated (see ). Tantalum hafnium carbide (TaHfC) is a refractory compound with a very high melting point of 4215 K (3942 °C, 7128 °F). At the other end of the scale, helium does not freeze at all at normal pressure even at temperatures close to absolute zero; a pressure of more than twenty times normal atmospheric pressure is necessary. Many laboratory techniques exist for the determination of melting points. A Kofler bench is a metal strip with a temperature gradient (range from room temperature to 300 °C). Any substance can be