columbite Meaning, Definition & Usage

  1. noun a black mineral that is an ore of niobium and tantalum
    niobite.

WordNet

Co*lum"bite noun
Etymology
Cf. F. colombite. See Columbium.
Definitions
  1. (Min.) A mineral of a black color, submetallic luster, and high specific specific gravity. It is a niobate (or columbate) of iron and manganese, containing tantalate of iron; -- first found in New England.

Webster 1913