'Yttro-columbite' definitions:

Definition of 'Yttro-columbite'

From: GCIDE

Yttro-columbite \Yt`tro-co*lum"bite\, Yttro-tantalite \Yt`tro-tan"ta*lite\, n. (Min.) A tantalate of uranium, yttrium, and calcium, of a brown or black color. [1913 Webster]