Metallic is only manufactured in small quantitiies, currently ca. 1 to 2^.10³ t/a worldwide. It is manufactured by the thermal reduction of calcium oxide with aluminum in vacuum at 1200°C:



the resulting calcium vapor being condensed. It is no longer produced by melt electrolysis.

Calcium is utilized in the manufacture of special metals such as zirconium, thorium, uranium and the rare earths, as a refining agent in metallurgy (steel, copper, magnesium, tantalum, lead) and in the manufacture of calcium hydride (hydrogen source).

Mining und Munufacture of Calcium and Calcium ate: calcium carbonate-containing minerals are mainly extracted by open-cast mining. High grade limestone is also extracted in underground workings. A comparatively small quantity of calcium carbonate is produced synthetically e.g. by carbonating calcium hydroxide solutions.