Argillites

Argillites: compact, densely layered sedimentary rocks composed of very fine particles that were transported in suspension in watercourses as powders and later deposited, forming mud or silt layers. The consolidation and solidification of these deposits led to the formation of argillites, commonly found in alluvial plains, river valleys, and ancient lake basins. Argillites are composed of Quartz, Micas, clay minerals, and Limestone fragments.

argillite
(Photo: James St. John/Flickr, License CC BY 2.0)

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