Niobium, formerly columbium, is a chemical element with the symbol Nb (formerly Cb) and atomic number 41. It is a soft, grey, ductile transition metal, which is often found in the pyrochlore mineral, the main commercial source for niobium, and columbite. The name comes from Greek mythology: Niobe, daughter of Tantalus.Symbol: Nb
Atomic number: 41
Electron configuration: Kr 4d4
Melting point: 2,469 °C
Atomic mass: 92.90638 ± 0.00002 u
Discoverer: Charles Hatchett