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-phyre

Porphyritic rocks.

A modification of the ending of German Porphyr, porphyry.

Porphyry is a hard igneous rock containing crystals of feldspar in a fine-grained, typically reddish groundmass; its name derives from Greek porphura, purple. Examples of the form include lamprophyre (Greek lampros, bright, shining), a porphyritic igneous rock with phenocrysts chiefly of biotite; granophyre, a granitic rock in which feldspar and quartz are intergrown; vitrophyre, any of a class of porphyritic rocks characterized by an igneous texture in which phenocrysts are embedded in a glassy groundmass.

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