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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 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]
In 1943, Berta Karlik and Traude Bernert found it in nature; due to World War II, they were initially unaware of Corson et al.'s results. [184] Horia Hulubei and Yvette Cauchois had previously claimed its discovery as a natural radioelement from 1936, naming it dor : they likely did have the isotope 218 At, and probably did have enough ...
For many years, there was confusion over whether columbium and tantalum were the same. In 1846, German chemist Heinrich Rose argued that there were two additional elements in tantalite, which he named niobium and pelopium for the children of the Cyclops. Eventually, Rose's niobium (atomic number 41) was found to be identical to Hatchett's ...
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.
Niobium can be found in aircraft gas turbines, vacuum tubes and nuclear reactors. An alloy used for liquid rocket thruster nozzles, such as in the main engine of the Apollo Lunar Modules, is C103, which consists of 89% niobium, 10% hafnium and 1% titanium. [27] Another niobium alloy was used for the nozzle of the Apollo Service Module. As ...