feldspar

Definitions of feldspar
  1. noun
    any of a group of hard crystalline minerals that consist of aluminum silicates of potassium or sodium or calcium or barium
    synonyms: felspar
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    types:
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    orthoclase
    a white or colored monoclinic feldspar
    oligoclase, plagioclase
    any of a series of triclinic feldspars that form rocks
    moonstone
    a transparent or translucent gemstone with a pearly luster; some specimens are orthoclase feldspar and others are plagioclase feldspar
    albite, white feldspar
    a widely distributed feldspar that forms rocks
    anorthite
    rare plagioclastic feldspar occurring in many igneous rocks
    type of:
    spar
    any of various nonmetallic minerals (calcite or feldspar) that are light in color and transparent or translucent and cleavable
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