igneous
Granite and Porphyry Pebbles
Intrusive Igneous Rock
Hardness of 6-7 on the Mohs scale, varied colors including pink, grey, and speckled black and white, vitreous to dull luster, granular crystal structure, specific gravity around 2.65-2.75.
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Physical properties
Hardness of 6-7 on the Mohs scale, varied colors including pink, grey, and speckled black and white, vitreous to dull luster, granular crystal structure, specific gravity around 2.65-2.75.
Formation & geological history
Formed from the slow cooling of magma rich in silica and alkali metals far beneath the Earth's surface over millions of years.
Uses & applications
Used widely in construction, dimension stone, monuments, countertops, and as decorative landscape rocks or collection specimens.
Geological facts
Granite is the most common intrusive rock of Earth's continental crust and is exceptionally durable against weathering.
Field identification & locations
Easily identified by its distinct interlocking mineral crystals of quartz, feldspar, and micas; commonly found in mountainous regions and glacial drift deposits worldwide.
