Extractive metallurgy
Properties of tungsten and its alloys

Tungsten, chemical symbol W, is a rare metal: its content in the earth's crust is estimated at 10^{– 6} by mass. Mineable mineral salts are scheelite CaWO₄ and wolframite (Fe, Mn)WO₄[2][3].

The average WO₃ wolfram anhydride content of current mining projects is 0.4%. The most abundant deposits are in the countries of the Pacific Ring of Fire. The European contribution is small: Portugal, Spain, France (Salau, Ariège), Austria and Sweden. Soviet deposits are found in the Urals, Altai, Caucasus and Siberia.

Recognized and probable, economically recoverable reserves were estimated in 1982 at 3.7 million tonnes of WO ₃...