Word Study
tantalite
CIDE DICTIONARY
tantalite, n. [Cf. F. tantalite.].
A heavy mineral of an iron-black color and submetallic luster. It is essentially a tantalate of iron. [1913 Webster]
OXFORD DICTIONARY
tantalite, n. a rare dense black mineral, the principal source of the element tantalum.
Etymology
G & Sw. tantalit (as TANTALUM)
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