columbite

English Thesaurus

1. a black mineral that is an ore of niobium and tantalum (noun.substance)

hypernym	:	mineral,
definition	:	solid homogeneous inorganic substances occurring in nature having a definite chemical composition (noun.substance)

substance holonym	:	atomic number 41, nb, niobium,
definition	:	a soft grey ductile metallic element used in alloys; occurs in niobite; formerly called columbium (noun.substance)

substance holonym	:	atomic number 73, ta, tantalum,
definition	:	a hard grey lustrous metallic element that is highly resistant to corrosion; occurs in niobite and fergusonite and tantalite (noun.substance)