Definition
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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
Granite is a very hard, granular, crystalline igneous rock which consists mainly of quartz, mica, and feldspar and is often used as building stone
From Italian granito, which means grained rock, from grano grain, and from Latin granum
Coarse Grained Rock, Opaque Rock