phyllite

American  

[fil-ahyt] / ˈfɪl aɪt /

noun

1. a slaty rock, the cleavage planes of which have a luster imparted by minute scales of mica.

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phyllite British  

/ ˈfɪlaɪt /

noun

1. a compact lustrous metamorphic rock, rich in mica, derived from a shale or other clay-rich rock

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phyllite Scientific  

/ fĭl′īt′ /

1. 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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Other Word Forms

• phyllitic
  adjective

Etymology

Origin of phyllite

First recorded in 1820–30; phyll- + -ite ¹

Example Sentences

See Examples For:

phyllite

Two years ago, I scrambled into a six-foot-deep soil pit dug into this hillside to examine the crumbling phyllite rock just below the topsoil.

From Washington Post ● May 10, 2019

The sequence slate → phyllite → schist → gneiss illustrates an increasing metamorphic grade.

From Textbooks ● Jan. 1, 2017

The rock sequence is sedimentary rock, slate, phyllite, schist, gneiss, migmatite, and granite.

From Textbooks ● Jan. 1, 2017

Where slate is typically planar, phyllite can form in wavy layers.

From Textbooks ● Jan. 1, 2015

The rocky cliffs, about eighty feet in height at the highest point, were formed of vertically lying slate rocks—a very uniform series of phyllite and sericite-schist.

From The Home of the Blizzard Being the Story of the Australasian Antarctic Expedition, 1911-1914 by Sir Douglas Mawson