igneous
Granite
Phaneritic Felsic Igneous Rock
Hardness: 6-7 (Mohs scale); Color: Salt and pepper (pinkish-brown and black grains); Luster: Vitreous to dull; Crystal structure: Phaneritic (coarse-grained); Cleavage: None (minerals within exhibit cleavage independently); Specific gravity: 2.63 - 2.75
- Hardness
- 6-7 (Mohs scale)
- Color
- Salt and pepper (pinkish-brown and black grains)
- Luster
- Vitreous to dull
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 (pinkish-brown and black grains); Luster: Vitreous to dull; Crystal structure: Phaneritic (coarse-grained); Cleavage: None (minerals within exhibit cleavage independently); Specific gravity: 2.63 - 2.75
Formation & geological history
Formed through the slow crystallization of magma below the Earth's surface (intrusive). The large grains indicate a long cooling period. It can date back over 4 billion years in the Earth's crust.
Uses & applications
Extensively used in construction for countertops, floor tiles, paving stones, curbing, monuments, and as aggregate for roads.
Geological facts
Granite makes up a large portion of the Earth's continental crust. Famous locations like Yosemite's Half Dome and Mount Rushmore are made entirely of granite.
Field identification & locations
Identify in the field by its visible interlocking crystals of quartz (clear/grey), feldspar (tan/pink), and mica (black/shiny). It is commonly found in mountain ranges and continental shields. Collectors look for unique mineral inclusions like tourmaline or large feldspar crystals.
