Word Study
hypersthene
CIDE DICTIONARY
hypersthene, n. [Gr. "ype`r over + sqe`nos strength: cf. F. hyperstène.].
An orthorhombic mineral of the pyroxene group, of a grayish or greenish black color, often with a peculiar bronzelike luster (schiller) on the cleavage surface. [1913 Webster]
OXFORD DICTIONARY
hypersthene, n. a rock-forming mineral, magnesium iron silicate, of greenish colour.
Etymology
F hyperst{egrave}ne (as HYPER-, Gk sthenos strength, from its being harder than hornblende
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