Tungsten. (Source: © Björn Wylezich / stock.adobe.com)

Chemical element with the atomic number 74. It is also called wolfram. Tungsten is a grey-white metal found on Earth in various minerals such as scheelite or wolframite. It is very hard, has a high density comparable to uranium and the highest melting point of all metals, 3,422 °C. It forms very hard and chemically inert compounds with carbon (tungsten carbide), boron, nitrogen, and silicon. It is used, for example, for the production of filaments for light bulbs or to increase the hardness of steel. In thermonuclear reactors, tungsten is used for lining highly heat-stressed parts, so-called plasma facing components like first wall or divertor.