igneous

Granite

Granite (composed of Quartz, Alkali Feldspar, and Plagioclase)

Hardness: 6-7 Mohs; Color: Gray, salt-and-pepper, or white with dark flecks; Luster: Vitreous to dull; Crystal structure: Phaneritic (coarse-grained crystalline); Cleavage: None (grains have individual cleavage); Specific gravity: 2.63-2.75

Hardness: 6-7 Mohs
Color: Gray, salt-and-pepper, or white with dark flecks
Luster: Vitreous to dull

Identified February 20, 2026More igneous →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Formed through the slow crystallization of magma below Earth's surface (intrusive). Most continental granite dates from the Precambrian to the Cenozoic eras, typically forming in continental arcs or orogenic belts.

Uses & applications

Widely used in construction for countertops, floor tiles, paving stones, curbing, and monuments due to its durability and resistance to weathering.

Geological facts

Granite makes up much of the Earth's continental crust. Famous landmarks like Mount Rushmore and Yosemite's Half Dome are composed entirely of granite.

Field identification & locations

Identify in the field by its coarse, interlocking crystalline texture where individual minerals (clear quartz, white/pink feldspar, dark mica) are visible to the naked eye. Found globally in mountainous regions and shield areas.

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

Magnetite

Iron(II,III) oxide (Fe3O4)

mineral

Blue Apatite

Apatite (Group), Ca5(PO4)3(F,Cl,OH)

mineral

Sodalite

Sodalite - Na8(Al6Si6O24)Cl2

mineral

Magnetite

Magnetite (Fe3O4)

mineral