igneous

Granite

Granite (Phaneritic Acidic Igneous Rock)

Hardness: 6-7 Mohs; Color: Salt-and-pepper (white/grey with black spots); Luster: Dull to vitreous; Crystal structure: Coarse-grained phaneritic; Cleavage: None (fractures); Specific gravity: 2.63 to 2.75

Hardness: 6-7 Mohs
Color: Salt-and-pepper (white/grey with black spots)
Luster: Dull to vitreous

Identified March 11, 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 the Earth's surface (intrusive). Commonly dates from the Precambrian to the Cenozoic era, found in continental crust and mountain ranges.

Uses & applications

Extensively used in construction for countertops, floor tiles, paving stones, curbing, and monuments. Highly valued for durability and aesthetics in architectural design.

Geological facts

Granite makes up a large portion of the Earth's continental crust. Mount Rushmore is carved out of a granite batholith. It is primarily composed of quartz, feldspar, and mica.

Field identification & locations

Identify by its interlocking 'salt-and-pepper' mineral grains and high hardness (it will scratch glass). Found globally in mountain cores. Collectors look for unique inclusions or pink/red orthoclase varieties.

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