Igneous

Granite

Granite (Felsic Plutonic Rock)

Hardness: 6-7 on Mohs scale; Color: Pink, grey, and black mottled; Luster: Vitreous to dull; Crystal structure: Phaneritic (coarse-grained); Cleavage: None (individual minerals like feldspar have cleavage, but the rock unit does not); Specific gravity: 2.65 - 2.75 g/cm³.

Hardness: 6-7 on Mohs scale
Color: Pink, grey, and black mottled
Luster: Vitreous to dull

Identified March 17, 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). Composed primarily of quartz, potassium feldspar (pink), and plagioclase feldspar, with minor amounts of mica or amphiboles (black).

Uses & applications

Extensively used in construction for countertops, floor tiles, paving stones, and monuments. It is also used in high-traffic commercial buildings due to its durability.

Geological facts

Granite makes up a large portion of the Earth's continental crust. It is one of the hardest natural stones in the world and has been used since ancient Egypt to build pyramids and temples.

Field identification & locations

Identify in the field by its 'salt and pepper' or mottled appearance with visible interlocking crystals. It is found in mountain ranges and continental shields worldwide. For collectors, common river-worn or tumbled specimens are easy to find.

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