igneous

Granite

Granite (Felsic Plutonic Rock)

Hardness: 6–7 on Mohs scale; Color: Mottled grey, white, and black; Luster: Phaneritic (crystalline) and vitreous; Crystal structure: Coarse-grained granular; Specific gravity: Approx 2.63 to 2.75.

Hardness: 6–7 on Mohs scale
Color: Mottled grey, white, and black
Luster: Phaneritic (crystalline) and vitreous

Identified March 22, 2026More igneous →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 6–7 on Mohs scale; Color: Mottled grey, white, and black; Luster: Phaneritic (crystalline) and vitreous; Crystal structure: Coarse-grained granular; Specific gravity: Approx 2.63 to 2.75.

Formation & geological history

Formed from the slow cooling of silica-rich magma deep underground (intrusive). They are primarily found in continental crust and can range in age from the Archean Eon to the Cenozoic Era.

Uses & applications

Extensively used in construction as dimension stone, countertops, floor tiles, and as crushed stone for road base and concrete aggregate.

Geological facts

Granite makes up a large portion of the Earth's continental crust. Famous peaks like Yosemite's Half Dome and Mount Everest's upper sections are composed of granite.

Field identification & locations

Identify by its 'salt and pepper' appearance and visible interlocking crystals of quartz, feldspar, and mica. Commonly found in mountain ranges and Shields (like the Canadian Shield). It will not be scratched by a steel knife.

Other igneous specimens

See all

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

mineral

Dark Igneous Rock (Likely Basalt or Diabase)

Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.

Igneous