مواد معدنی/Bauxite

an aluminium ore, is the World ̍ s main source of aluminium. It consists mostly of the minerals gibbsite ( AL(OH)3) , boehmite (γ-AlO(OH)) and diaspore (α-AlO(OH)), mixed with the two iron oxides goethite and haematite, the clay mineral kaolinite and small amounts of anatase (TiO2) and ilmenite (FeTiO3 or FeO.TiO2). Bauxite is usually strip mined because it is almost always found near the surface of the terrain, with little or no overburden. As of 2010, approximately 70% to 80% of the Worl ̍ s dry bauxite production is processed first into alumina and then into aluminium by electrolysis. Bauxite rocks are typically classified according to their intended commercial application: metallurgical, abrasive, cement, chemical, and refractory.