bauxite and alumina 1999 10 1 b auxite a lumina by patricia plunkert domestic survey data tables were prepared micheal george statistical assistant the world production regina r coleman international coordinator is naturally occurring heterogeneous material comprised primarily of one or more aluminum hydroxide minerals plus various mixtures silica sio 2 iron oxide fe o 3 titania tio aluminosilicates clay etc other impurities in trace amounts principal found varying proportions within are gibbsite al oh polymorphs boehmite diaspore both alo typically classified according to its intended commercial application such as abrasive cement chemical metallurgical refractory all mined approximately 85 converted for metal an additional goes nonmetal uses forms specialty remaining 5 used nonmetallurgical applications bulk therefore feed manufacture via wet caustic leach process known bayer majority
