igneous
Granite
Phaneritic Felsic Igneous Rock
Hardness of 6 on the Mohs scale; speckled pink, white, gray, and black color; vitreous to dull luster; phaneritic (coarse-grained) crystal structure; composed primarily of quartz, alkali feldspar, and plagioclase with biotite and amphibole; specific gravity around 2.65 to 2.75.
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Physical properties
Hardness of 6 on the Mohs scale; speckled pink, white, gray, and black color; vitreous to dull luster; phaneritic (coarse-grained) crystal structure; composed primarily of quartz, alkali feldspar, and plagioclase with biotite and amphibole; specific gravity around 2.65 to 2.75.
Formation & geological history
Formed from the slow cooling and crystallization of magma rich in silica and alkali metal oxides beneath the Earth's surface over millions of years.
Uses & applications
Widely used in construction for dimension stone, architectural facings, floor tiles, counter tops, and monuments.
Geological facts
Granite is the most common rock of the Earth's continental crust and forms the core of many major mountain ranges.
Field identification & locations
Easily identified by its distinct interlocking, coarse-grained crystals of pink/white feldspar, glassy clear quartz, and dark biotite or hornblende. Found globally in shield areas and mountainous regions.
