niobium

A silvery, soft, rare, ductile metallic element that occurs chiefly in columbite-tantalite and is used in steel alloys, arc welding, and superconductive materials. Atomic number 41; atomic weight 92.906; melting point 2,477°C; boiling point 4,744°C; specific gravity 8.57; valence 2, 3, 5. cross-reference: Periodic Table.

Chemical symbol, Nb; atomic weight, 94. A metal of steel-gray color and brilliant luster.

The chemical element of atomic number 41. Chemical symbol Nb. Atomic weight 92.91. Previously called columbium. See also columbium.

a metallic chemical element (symbol Nb) with an atomic number of 41.

a soft grey ductile metallic element used in alloys; occurs in niobite; formerly called columbium