igneous
Granite
Granite (Phaneritic Quartz-Feldspar-Biotite rock)
Hardness: 6-7 (Mohs scale), Color: Salt-and-pepper (white, gray, black), Luster: Vitreous to dull, Crystal structure: Phaneritic (visible crystals), Cleavage: None (grains have cleavage, rock fractures irregularly)
Identified More igneous →
Explore Granite in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-7 (Mohs scale), Color: Salt-and-pepper (white, gray, black), Luster: Vitreous to dull, Crystal structure: Phaneritic (visible crystals), Cleavage: None (grains have cleavage, rock fractures irregularly)
Formation & geological history
Formed by the slow cooling and crystallization of magma beneath the Earth's surface (intrusive igneous). It can be billions of years old, often found in the cores of mountain ranges.
Uses & applications
Extensively used in construction for countertops, floor tiles, paving stones, curbing, monuments, and as crushed stone for road base.
Geological facts
Granite makes up a large portion of the Earth's continental crust. It is extremely durable and resistant to erosion, which is why it often forms the peaks of mountains like the Sierra Nevada.
Field identification & locations
Identify by its interlocking 'salt and pepper' crystalline texture where minerals are large enough to see with the naked eye. Commonly found in continental mountain ranges and shield areas. Excellent for beginners to practice identifying quartz, feldspar, and mica.
