- a slaty rock, the cleavage planes of which have a luster imparted by minute scales of mica.
Origin of phyllite
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for phyllite
Geologically, the Erzgebirge range consists mainly of gneiss, mica and phyllite.
- a compact lustrous metamorphic rock, rich in mica, derived from a shale or other clay-rich rock
C19: from phyll (o) - + -ite 1
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- A green, gray, or red metamorphic rock, similar to slate but often having a wavy surface and a distinctive luster imparted by the presence of mica.
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