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Niobium is estimated to be the 33rd most abundant element in the Earth's crust, at 20 ppm. [46] Some believe that the abundance on Earth is much greater, and that the element's high density has concentrated it in Earth's core. [33] The free element is not found in nature, but niobium occurs in combination with other elements in minerals. [40]
The mineral columbite The element niobium. In 1846, Rose rediscovered the chemical element niobium, proving conclusively that it was different from tantalum. This confirmed that Charles Hatchett had discovered niobium in 1801 in columbite ore. Hatchett had named the new element "columbium", from the ore in which niobium and tantalum coexist.
Perey discovered it as a decay product of 227 Ac. [177] Francium was the last element to be discovered in nature, rather than synthesized in the lab, although four of the "synthetic" elements that were discovered later (plutonium, neptunium, astatine, and promethium) were eventually found in trace amounts in nature as well. [178]
Niobium is a chemical element with symbol Nb and atomic number 41. A rare, soft, grey, ductile transition metal , niobium is found in the minerals pyrochlore (the main source for niobium) and columbite .
Tantalum was discovered in Sweden in 1802 by Anders Ekeberg, in two mineral samples – one from Sweden and the other from Finland. [15] [16] One year earlier, Charles Hatchett had discovered columbium (now niobium). [17] In 1809, the English chemist William Hyde Wollaston compared the oxides of columbium and tantalum, columbite and tantalite.
The main source of niobium until now has been from the ore mineral columbite that is extracted widely in Canada, Brazil, Australia and Nigeria, with China obtaining nearly 95 per cent of the ...
Archaeologists discovered it on the skeleton of a man buried in a cemetery in the Roman city of Nida, one of the largest and most important sites in the central German state of Hesse.
In subsequent decades, superconductivity was found in several other materials; In 1913, lead at 7 K, in 1930's niobium at 10 K, and in 1941 niobium nitride at 16 K. In 1933, Walther Meissner and Robert Ochsenfeld discovered that superconductors expelled applied magnetic fields, a phenomenon that has come to be known as the Meissner effect.