argillite(redirected from argillitic)
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A metamorphic rock, intermediate between shale and slate, that does not possess true slaty cleavage.
[Latin argilla, argil; see argil + -ite.]
(Geological Science) any argillaceous rock, esp a hardened mudstone
[C18: from Latin argilla clay (from Greek argillos) + -ite1]
any compact sedimentary rock composed mainly of clay materials; clay stone.
[1785–95; < Latin argill(a) clay (< Greek árgillos, derivative of argós white) + -ite1]
ar`gil•lit′ic (-ˈlɪt ɪk) adj.