tantalite
Tan"ta*lite, n. Etym: [Cf. F. tantalite.] (Min.) Defn: A heavy mineral of an iron-black color and submetallic luster. It is essentially a tantalate of iron.
Tan"ta*lite, n. Etym: [Cf. F. tantalite.] (Min.) Defn: A heavy mineral of an iron-black color and submetallic luster. It is essentially a tantalate of iron.