Related formsar·gil·lit·ic [ahr-juh-lit-ik] /ˌɑr dʒəˈlɪt ɪk/, adjective
Examples from the Web for argillite
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.
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
It is very significant that we never find one where the workman used both flint and argillite.The Prehistoric World|E. A. Allen