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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]
argillitic adj


(ˈɑr dʒəˌlaɪt)

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.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.argillite - a sedimentary rock differing from shale in being bound by silica and from slate in having no slate cleavages
sedimentary rock - rock formed from consolidated clay sediments
References in periodicals archive ?
The gallery includes Totem Hall, Nisga'a: People of the Nass River, Jonathan Hunt House, Haida Argillite Carving, and Archaeolgy.
The studied rocks were concentrated biotite ("biotite") (Mogi das Cruzes, Sao Paulo State), nepheline syenite ("syenite") (Pocos de Caldas plateau, Minas Gerais State), and green banded argillite ("argillite") (Cedro de Abaete region, Minas Gerais State).
Compared with compositions of many other oil shales of the world [7], including the Estonian Paleozoic kukersite [14], and graptolite argillite [15-18], the Near East oil shales have specifically high contents of carbonate (calcite), silica (quartz, in places with admixture of tridymite and cristobalite--unpublished data by the authors) and sulfur [8].
This year, Andra plans to present the French government and nuclear regulator ASN a technical dossier on Bure, which aims to bury nuclear waste 500 meters underground in thick layers of argillite rock, which Andra says will prevent most radioactive particles from traveling more than a few meters over hundreds of thousands of years.
Found in British Columbia's Haida Gwaii archipelago, the slatelike black argillite rock is soft enough for Haida artists to carve tribal mythology stories by hand, yet hard enough to register beautiful details.
2] clay deposit in the Gaspe area using a proprietary process to extract alumina and other by-products from argillite.
Characteristically, different (up to 5) decimetric beds of conglomerate are recognised within the argillite units.
Reddish argillite and siltic interbeds can be found as imprinting a parallel lamination-type structure (Fig.
Daxhiigang, in particular, was a highly skilled argillite and black slate carver, and his miniature totem poles, small animal statues, and carved boxes have been collected widely (16.
The deposit also contains a fair amount of argillite, a lighter form of trap rock which is permitted for mining as well.