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In 1809, English chemist William Hyde Wollaston compared the oxides derived from both columbium—columbite, with a density 5.918 g/cm 3, and tantalum—tantalite, with a density over 8 g/cm 3, and concluded that the two oxides, despite the significant difference in density, were identical; thus he kept the name tantalum. [16]
The mineral group tantalite [(Fe, Mn)Ta 2 O 6] is the primary source of the chemical element tantalum, a corrosion (heat and acid) resistant metal. It is chemically similar to columbite , and the two are often grouped together as a semi-singular mineral called coltan or "columbite-tantalite" in many mineral guides.
Coltan (short for columbite–tantalites and known industrially as tantalite) is a dull black metallic ore from which the elements niobium and tantalum are extracted. The niobium-dominant mineral in coltan is columbite (after niobium's original American name columbium), and the tantalum-dominant mineral is tantalite. [1] Tantalum from coltan is ...
Tantalite (Fe, Mn)Ta 2 O 6 is the most important mineral for tantalum extraction. Tantalite has the same mineral structure as columbite (Fe, Mn) (Ta, Nb) 2 O 6; when there is more tantalum than niobium it is called tantalite and when there is more niobium than tantalum is it called columbite (or niobite).
In 1809, English chemist William Hyde Wollaston compared the oxides derived from both columbium—columbite, with a density 5.918 g/cm 3, and tantalum—tantalite, with a density over 8 g/cm 3, and concluded that the two oxides, despite the significant difference in density, were identical; thus he kept the name tantalum. [14]
Apollo CSM with the dark rocket nozzle made from niobium-titanium alloy . Niobium is nearly always found together with tantalum, and was named after Niobe, the daughter of the mythical Greek king Tantalus for whom tantalum was named. Niobium has many uses, some of which it shares with other refractory metals.
In 1809, W. H. Wollaston claimed that columbium and tantalum are identical, which proved to be false. [84] In 1844, Heinrich Rose proved that the elements were distinct and renamed columbium to niobium (Niobe is the daughter of Tantalus). [108] De Marignac's sample contained impurities; relatively pure tantalum was produced by Werner von Bolton ...
Tantalum, niobium, and rare-earth elements are sourced from a few pegmatites worldwide, such as the Greenbushes Pegmatite, [30] the Kibara Belt of Rwanda and Democratic Republic of the Congo, the Kenticha mine of Ethiopia the Alto Ligonha Province of Mozambique, [31] and the Mibra (Volta) mine of Minas Gerais, Brazil. [32]