Definition
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Discoverer
Etymology
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Other Categories
Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture
From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use
Fine Grained Rock, Opaque Rock
Schist is a medium grade metamorphic rock with medium to large, flat, sheet like grains in a preferred orientation
From French schiste, Greek skhistos i.e. split
Durable Rock, Medium Hardness Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock