Columbite, also known as Niobite or Niobite-Tantalite, is a black mineral that is an ore of Niobium and Tantalum. It has a sub-metallic luster and a high specific gravity. It is a Niobate of Iron and Manganese which contains Tantalate of Iron. Columbite has the same composition and crystal symmetry as Tantalite but the latter has a much greater specific gravity. It is used for heat resistance.