igneous

Granite

Granite (Phaneritic Igneous Rock; primarily Quartz, Alkali Feldspar, and Plagioclase)

Hardness: 6-7 on Mohs scale; Color: typically mottled grey, white, pink, or tan; Luster: Vitreous to dull; Crystal structure: Phaneritic (coarse-grained, visible crystals); Specific gravity: 2.63 to 2.75.

Hardness: 6-7 on Mohs scale
Color: typically mottled grey, white, pink, or tan
Luster: Vitreous to dull

Identified March 23, 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 from the slow cooling and crystallization of magma deep beneath the Earth's surface (plutonic). It can range from Precambrian to Cenozoic ages and is the primary component of continental crust.

Uses & applications

Extensively used in construction as dimension stone for countertops, flooring, and cladding. Also used in infrastructure as crushed stone, and occasionally polished for decorative items.

Geological facts

Granite makes up the core of most continental mountain ranges. The famous faces on Mount Rushmore are carved into a massive granite batholith in South Dakota.

Field identification & locations

Identified in the field by its 'salt and pepper' appearance and visible interlocking crystals of quartz and feldspar. Found globally in continental shield areas and mountain ranges like the Sierra Nevada or the Rockies.

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

Sodalite

Sodalite - Na8(Al6Si6O24)Cl2

mineral

Blue Apatite

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

mineral

Magnetite

Magnetite (Fe3O4)

mineral