In its pure form, magnesium is a silvery grey, very light metal, which corrodes easily and is also highly inflammable. When alloyed with other metals however, principally aluminium and copper, it produces a very light, strong material, which has a range of uses in motor vehicles, aircraft and space craft. The principal ore of magnesium is magnesite, or magnesium carbonate, which also has a range of uses in its own right. Australia has the fourth largest world reserves of magnesite, with production coming mainly from the huge deposit at Kunwarara in central Queensland. In NSW, the deposit at Thuddungra near Young, contains the world's highest grade magnesite.
Deposits also exist in Tasmania and the Northern Territory.
Manganese The chief ore of manganese is pyrolusite or manganese dioxide, which is mined at Groote Eylandt in the Northern Territory. Other reserves exist in the Pilbara region. Australia is the third largest producer of manganese, which supplies both domestic needs and a substantial export market. Manganese compounds are powerful oxidising agents and are used in the manufacture of a range of chemicals, including chlorine and oxygen gases. Mercury Mercury is a heavy, bright silver metal which is liquid at normal temperatures and is a good conductor of electricity.