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Webster 1828 Edition

Noun.

[Gr. to shine.] A beautiful species of alabaster, superior in brightness to most species of marbles.

phengite ‎(countable and uncountable, plural phengites)

(mineralogy) Any of a series of dioctahedral micas of composition K(AlMg)₂(OH)₂(SiAl)₄O₁₀, similar to muscovite but with addition of magnesium.