igneous
Granite with Biotite and Iron Oxide
Intrusive Igneous Rock
AI-generated identification · may be incorrectHardness 6-7 on Mohs scale, multicolored with grey, brown, and black grains, sub-metallic to dull luster, phaneritic crystal structure.
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Physical properties
Hardness 6-7 on Mohs scale, multicolored with grey, brown, and black grains, sub-metallic to dull luster, phaneritic crystal structure.
Formation & geological history
Formed from the slow cooling of magma beneath the Earth's surface over millions of years.
Uses & applications
Used in construction, monuments, countertops, and as crushed stone for road bases.
Geological facts
Granite forms the core of many major mountain ranges and is one of the most abundant rocks in the continental crust.
Field identification & locations
Identify by visible interlocking mineral crystals of quartz, feldspar, and dark mica flecks; found worldwide in shield areas and mountain roots.
