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orthopyroxene

noun

a member of the pyroxene group of minerals having an orthorhombic crystal structure, such as enstatite and hypersthene
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Science definitions for orthopyroxene

orthopyroxene

[ôr′thə-pī-rŏk′sēn′]

Any variety of the mineral pyroxene that crystallizes in the orthorhombic system and contains no calcium and little or no aluminum. Enstatite is an orthopyroxene.
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