Definition
Coquina is a sedimentary rock that is composed either wholly or almost entirely of the transported, abraded, and mechanically-sorted fragments of the shells of molluscs, trilobites, brachiopods, or other invertebrates
Argillites are highly compact sedimentary or slightly metamorphosed rocks that consist largely or wholly of particles of clay or silt but lack the fissility of shale or the cleavage characteristic of slate
History
Origin
European Foreland Basins
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Discoverer
Unknown
Unknown
Etymology
From Concha (Latin)+ Coquina(Spanish) +conch(English)= Couquina (mid 19th century)
From Latin Argilla (clay) and -ite in English which became agrilla+ -ite = Argillite
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Soft Rock
Family
Group
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Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock