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Origin With an occurrence of about 0.021 % within the earth crust, zirconium is the 20th most abundant element of the periodic system. It is only found in a fully oxidized state, never as a free metal. The over 40 known minerals can be roughly grouped in zirconium orthosilicates, zirconium dioxide, zirconsilicates (with Na, Ca, Fe and other elements), zirconium carbonates (with Na, Ca and other elements) and others. The commercially most important mineral is zircon ZrSiO4, which contains contaminations of Hf, Fe2O3 and CaO. The ore is recovered from sand deposits in coastal areas of Australia, Florida, South Africa, India, Russia and Kazakhstan. Apart from zircon, baddeleyite ZrO2 and eudialyte (Ca,Na2)6(Zr,Fe)(Si3O9)2(OH,Cl)2 are also commercially employed. Zirconium metal powder is usually produced by reducing zirconium dioxide ZrO2. ZrO2 is either supplied as baddeleyite, or obtained by caustic fusion of zircon in a sodium hydroxide melt.