plagioclase: Meaning and Definition of


Pronunciation: (plā'jē-u-klās"), [key]
— n.
  1. any of the feldspar minerals varying in composition from acidic albite, NaAlSiO, to basic anorthite, CaAlSiO, found in most igneous rocks: shows twinning striations on good cleavage surfaces. Also called
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
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