| Melcher, F., Graupner, T., Sitnikova, M., Henjes-Kunst, F., OberthĂŒr, T., GĂ€bler, H.-E, Bahr, A., Gerdes, A., BrĂ€tz, H., Rantitsch, G. (2009) Ein Herkunftsnachweis fĂŒr Niob-Tantalerze am Beispiel afrikanischer Selten-Element Pegmatite. Mitteilungen der Ăsterreichischen Mineralogischen Gesellschaft, 155. | Journal (article/letter/editorial) | of minerals, commonly dominated by columbite-tantalite group minerals. In cases, their compositions and...measured in a representative number of columbite-tantalite grains from a given sample. Some elements, e.g...Coltan), orthorhombische Mischkristalle der Reihe [(Fe,Mn)(Nb,Ta)2 O6 ]. Sie sind durch hohe Dichten (5,3-8...(columbite-tantalite group minerals = CGM) werden je nach Zusammensetzung mit den SufïŹxen (-Fe) und (-Mn) belegt;...La/Li-VerhĂ€ltnisse und CsGehalte, und in CGM durch Mn/Fe- und Ta/Nb-VerhĂ€ltnisse wiedergegeben (vgl. SIMMONS | | Graupner, T., Melcher, F., GĂ€bler, H.-E., Sitnikova, M., BrĂ€tz, H., Bahr, A. (2010) Rare earth element geochemistry of columbite-group minerals: LA-ICP-MS data. Mineralogical Magazine, 74 (4) 691-713 doi:10.1180/minmag.2010.074.4.691 | Journal (article/letter/editorial) | concentrations and distribution patterns of columbite-tantalite minerals from Ta-ore provinces worldwide are presented...melt in a pegmatite body (either Nb ? Ta or Fe ? Mn fractionation lines, or both) results in smaller...melt. In general, CGM from each individual Ta-ore province are characterized by a predominance of one type...K EY WORDS : LCT family pegmatites, columbite-tantalite, REE geochemistry, LA-ICP-MS data. Introduction...internal standard; for microlite, 44Ca was used. The Mn and Ca concentrations of each sample spot were previously | | Melcher, Frank, Graupner, Torsten, GĂ€bler, Hans-Eike, Sitnikova, Maria, Henjes-Kunst, Friedhelm, OberthĂŒr, Thomas, Gerdes, Axel, Dewaele, Stijn (2015) Tantalumâ(niobiumâtin) mineralisation in African pegmatites and rare metal granites: Constraints from TaâNb oxide mineralogy, geochemistry and UâPb geochronology. Ore Geology Reviews, 64. 667-719 doi:10.1016/j.oregeorev.2013.09.003 | Journal (article/letter/editorial) | Petrologie und Geochemie, UniversitĂ€t Frankfurt, NU b Altenhöferallee 1, D-60438 Frankfurt am Main, Germany...Radiometric data 4.4.2.2. Mineralogy 4.4.3. Alto-Ligonha Province (northern Mozambique) 4.4.3.1. Radiometric data...Mineralogy NU 5. Mineral chemistry of columbite-tantalite, tapiolite, wodginite and ixiolite in African...Pegmatites of Ethiopia and Somalia 5.4.3. Alto-Ligonha Province (Mozambique) 5.4.4. Damara Belt (Namibia) 5.4...sources 7.2. Compositional variation of columbite-tantalite, tapiolite and wodginite-ixiolite 7.3. Chemical | | | Journal (article/letter/editorial) | Kenticha mine (Ethiopia) and in the Alto Ligonha Province (Mozambique). Production from pegmatites and related...Plateau (Nigeria);  Mn-rich columbite-tantalite is typical of the Alto Ligonha Province (Mozambique), the...Arabian-Nubian Shield (Egypt, Ethiopia) and the Tantalite Valley pegmatites (southern Namibia) and  Large...Large compositional variations through Fe-Mn fractionation, followed by Nb-Ta fractionation are typical...Congo (DRC), Mozambique, Ethiopia, Nigeria and Burundi (Table 1). Notably, the majority of production |
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