- any compact sedimentary rock composed mainly of clay materials; clay stone.
Origin of argillite
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for argillite
It is very significant that we never find one where the workman used both flint and argillite.The Prehistoric World
E. A. Allen
Next above the Altyn lies thirty-four hundred feet of Appekunny argillite, or dull-green shale.The Book of the National Parks
Robert Sterling Yard
The fact that argillite continued in use until the very last does not affect this conclusion.
Sandstone may be converted into quartzite, and shale into argillite, a compact, massive clay rock.The Elements of Geology
William Harmon Norton
Here anthracitiferous coal is found in beds of argillite and sandstone.
- any argillaceous rock, esp a hardened mudstone
C18: from Latin argilla clay (from Greek argillos) + -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 highly compacted sedimentary or slightly metamorphic rock consisting primarily of particles of clay or silt. Argillite differs from mudstone in that it does not have the same fine laminations, and from shale and slate in that it is not fissile.
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