Definition
Origin
Discoverer
Etymology
Class
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Other Categories
Sandstone is defined as a rock which is composed of sand-sized grains of various minerals mostly of uniform size and often are smooth and rounded
From its composition, sand and stone
Coarse Grained Rock, Fine Grained Rock, Opaque Rock
Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix
From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites
Fine Grained Rock, Opaque Rock