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Webster 1913 Edition

(fā′al-īt)

Noun.

[So called from the island

Fayal

(Min.)

A black, greenish, or brownish mineral of the chrysolite group. It is a silicate of iron.

Fayalite

fayalite ‎(countable and uncountable, plural fayalites)

(mineralogy) Yellow, olive green, brown or black mineral with orthorhombic crystals of the olivine group, Fe₂Si O₄.

↑ Richard V. Gaines, H. Catherine W. Skinner, Eugene E. Foord, Brian Mason, and Abraham Rosenzweig: Dana's new mineralogy, John Wiley & Sons, 1997