tantalite

A black to red-brown mineral, (Fe,Mn)(Ta,Nb)₂O₆, distinguished from columbite by the predominance of tantalum over niobium and used as an ore of both elements.

A rare mineral, occurring crystallized and massive, of an iron-black color and submetallic luster.

A heavy mineral of an iron-black color and submetallic luster. It is essentially a tantalate of iron.

A dark-brown mineral that is an ore of tantalum and niobium, of the chemical formula (Fe, Mn) Ta2O6.

a mineral consisting of tantalum oxide of iron and manganese that occurs with niobite or in coarse granite; an ore of tantalum