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n. A silvery, soft, ductile metallic element that occurs chiefly in columbite-tantalite and is used in steel alloys, arc welding, and superconductivity research. Atomic number 41; atomic weight 92.906; melting point 2,468°C; boiling point 4,927°C; specific gravity 8.57; valence 2, 3, 5. See Table at element.

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

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

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

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

"Brazil's Companhia Brasileira de Metalurgia e Mineraçào, or CBMM as it is known, produces more than 80% of the world's supply of niobium, which is used to strengthen steel and is widely employed in making cars and natural-gas pipelines."

metallic element    metal   

columbium   

columbium   

columbium   

tungsten    tantalum    vanadium    beryllium    strontium    gallium    chromium    scandium    nanocrystalline    bauxite