m Ві , and tantalum -tantalite, with a density 7.935 g/cm Ві , and concluded that the two oxides, despite the significant difference in density, were identical; thus he kept the name tantalum. This conclusion was disputed in 1846 by the German chemist Heinrich Rose, who argued that there were two different elements in the tantalite sample, and named them after children of Tantalus: niobium (from Niobe, the goddess of tears), and pelopium (from Pelops ). This confusion arose from the minimal observed differences between tantalum and niobium. Both tantalum and niobium react with chlorine and traces of oxygen, including atmospheric concentrations, with niobium forming two compounds: the white volatile niobium pentachloride (NbCl5) and the non-volatile niobium oxychloride (NbOCl3). The claimed new elements pelopium, ilmenium and dianium were in fact identical to niobium or mixtures of niobium and tantalum.differences between tantalum and niobium were unequivocally demonstrated in 1864 by Christian Wilhelm Blomstrand, and Henri Etienne Sainte-Claire Deville, as well as Louis J . Troost, who determined the formulas of some of the compounds in 1865 and finally by the Swiss chemist Jean Charles Galissard de Marignac in 1866, who all proved that there were only two elements. These discoveries did not stop scientists from publishing articles about ilmenium until 1871. De Marignac was the first to prepare the metal in 1864, when he reduced niobium chloride by heating it in an atmosphere of hydrogen.de Marignac was able to produce tantalum-free niobium on an increased scale by 1866, it was not until the early 20th century that niobium was first used commercially, in incandescent lamp filaments. This use quickly became obsolete through the replacement of niobium with tungsten, which has a higher melting point and thus is preferable for use in incandescent lamps. The discovery that niobium improves the strength of steel was made in the 1920s, and this remains its predominant use. In 1961 the American physicist Eugene Kunzler and coworkers at Bell Labs discovered that niobium-tin continues to exhibit superconductivity in the presence of strong electric currents and magnetic fields, making it the first material known to support the high currents and fields necessary for making useful high -power magnets and electrically powered machinery. This discovery would allow-two decades later-the production of long multi-strand cables that could be wound into coils to create large, powerful electromagnets for rotating machinery, particle accelerators, or particle detectors. (Symbol Cb) was the name originally given to this element by Hatchett, and this name remained in use in American journals-the last paper published by American Chemical Society with columbium in its title dates from 1953-while niobium was used in Europe. To end this confus...