igneous

Granite

Hardness: 6-7 on Mohs scale; Color: Salt-and-pepper (white, gray, black); Luster: Phaneritic (visible crystals), dull to vitreous; Structure: Massive, granular; Cleavage: None (fractures); Specific Gravity: 2.63 - 2.75

Hardness: 6-7 on Mohs scale
Color: Salt-and-pepper (white, gray, black)
Luster: Phaneritic (visible crystals), dull to vitreous

Identified April 3, 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 crystallization of magma below Earth's surface (intrusive). Composed mainly of quartz, feldspar, and mica. Geological age can range from Precambrian to Cenozoic.

Uses & applications

Extensively used in construction for countertops, floor tiles, paving stone, curbing, and monuments. Also used as crushed stone for road base and railroad ballast.

Geological facts

Granite makes up a large portion of the Earth's continental crust. It is one of the hardest and most durable natural stones, which is why it has been used since ancient Egypt for monuments like the Great Pyramid's King's Chamber.

Field identification & locations

Identify by its interlocking 'salt and pepper' crystalline texture where minerals like clear quartz, white/pink feldspar, and black biotite mica are visible to the naked eye. Commonly found in mountain ranges and continental shields.

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