Question: the metal niobium has a?
Answer: Density (near r.t. ) Niobium, also known as columbium, is a chemical element with the symbol Nb (formerly Cb) and atomic number 41. Niobium is a light grey, crystalline, and ductile transition metal. Pure niobium has a hardness similar to that of pure titanium, and it has similar ductility to iron.