Niobium
Niobium, formerly columbium, is a chemical element with symbol Nb and atomic number 41. It is a soft, grey, ductile transition metal, often found in the minerals pyrochlore and columbite.
Atomic Weight: 92.90637 Density: 8.57 g/cm3 Melting Point: 2477 °C Boiling Point: 4744 °C