Tungsten

Tungsten was recognised in 1781 by Carl Wilhelm Scheele, who identified its acid in the mineral now called scheelite, and isolated in 1783 by the Spanish brothers Juan Jose and Fausto Elhuyar. Its English name comes from the Swedish tung sten, heavy stone; its chemical symbol W and its name in many languages come from wolfram, after the ore wolframite. Tungsten has the highest melting point of any metal and was long the material of light-bulb filaments. Dense and hard as well as heat-resistant, it is used in the tungsten carbide of cutting tools and drill bits, in electrical contacts and heating elements, and in armour-piercing shot, besides its former role as the glowing filament of incandescent lamps.

Tungsten only became practical as a light-bulb filament after William Coolidge at General Electric developed, around 1910, a process for making the intensely brittle metal ductile enough to draw into fine wire, a breakthrough that let tungsten displace the earlier, far more fragile carbon and osmium filaments and that underpinned the incandescent light bulb industry for most of the twentieth century, before efficiency regulations began phasing the technology out from the 2010s onward.

Tungsten carries two names and, in the older one, a scrap of folklore. Wolfram, the source of the symbol W, derives from the German for wolf's froth or wolf's cream, a name medieval tin-smelters gave to the troublesome ore wolframite because it interfered with the smelting of tin, seeming to devour the tin ore as a wolf devours sheep, leaving a frothy slag. The metal itself has no planetary or alchemical station, being an eighteenth-century discovery, but this metallurgical curse-name preserves the same imaginative habit that gave cobalt its goblin and nickel its devil: the personification of an obstinate ore as a hungry beast. The heavy stone that names it in English marks the density that first set it apart.

In recent decades tungsten carbide has also become a popular material for men's wedding rings, prized for a scratch resistance far exceeding gold or platinum, though the same hardness means such rings, unlike softer metals, cannot be resized and will shatter rather than bend if struck hard enough, a practical trade-off jewellers routinely explain to buyers. The rings owe their dark grey sheen to the same dense, wolf-named ore chemistry that once frustrated medieval tin-smelters.