n. A glassy, usually yellowish gray variety of orthopyroxene having a magnesium silicate base, mainly MgSiO3, usually found embedded in igneous rocks and meteorites. [Greek enstatēs, adversary (because of its refractory quality) : en-, in, at, near; see EN-2 + -statēs, one that stands; see stā- in the Appendix of Indo-European roots + -ITE1.] |
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