BASTNÄSITE
BASTNÄSITE Bastnäsites are rare carbonates that form rare earth element (REE) ores. The Bastnäsite Group consists of: bastnäsite-(Ce) – (Ce(CO3)F),bastnäsite-(La) – (La(CO3)F),bastnäsite-(Nd) – (Nd(CO3)F),bastnäsite-(Y) – (Y(CO3)(OH)),hydroxylbastnäsite-(Ce) – (Ce(CO3)(OH)),hydroxylbastnäsite-(Nd) – (Nd(CO3)OH) andthorbastnäsite-(Ce) – (ThCa(CO3)2F2.3H2O). The physical properties vary little among the members. It is not possible to differentiate the members of the Group under a microscope.The […]
BAUXITE
BAUXITE Bauxite is a rock composed of the minerals diaspore – α-AlO(OH), boehmite – γ-AlO(OH) and gibbsite – Al(OH)3, mixed with the iron oxides goethite and hematite, with the clay mineral kaolinite and, in small amounts, anatase – TiO2 and other minerals. Bauxite is the main aluminum ore and lateritic bauxites (siliceous bauxites) are distinguished […]
BIOTITE
BIOTITE Biotite – K(Fe2+/Mg)2(Al/Fe3+/Mg)([Si/Al]Si2O10)(OH/F)2 – is a very common phyllosilicate, occurring in igneous rocks (both intrusive and extrusive) and in metamorphic and sedimentary rocks. It is an important industrial mineral with many different applications. “Biotite” is not actually a mineral, but just a generic term that applies to minerals that make up a Series or […]