Search results
Results From The WOW.Com Content Network
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.
Niobium was officially adopted as the name of the element in 1949, but the name columbium remains in current use in metallurgy in the United States. It was not until the early 20th century that niobium was first used commercially. Niobium is an important addition to high-strength low-alloy steels.
A piece of columbite–tantalite, size 6.0 × 2.5 × 2.1 cm. 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 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 ...
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 .
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.
During the Second Congo War, Lueshe was the only operating industrial mine in the RCD's territory, producing 270 tons of semi processed niobium a month to sell to GfE. [9] Between July 2000 and September 2004, when the mine was shuttered, the mine produced 3,365.1 tons of concentrate, which was exported to the world market via another company ...
Hatchett found the element in columbite ore and named it columbium. In 1809, W. H. Wollaston claimed that columbium and tantalum are identical, which proved to be false. [85] Heinrich Rose proved in 1844 that the element is distinct from tantalum, and renamed it niobium.