Granite

Granite (composed primarily of Quartz SiO2, Feldspar KAlSi3O8, and Mica K(Mg,Fe)3AlSi3O10(OH)2)

Rock Type: igneous

Granite

Physical Properties

Hardness: 6-7 on Mohs scale; Color: Pink, white, and grey; Luster: Vitreous to dull; Crystal structure: Phaneritic (coarse-grained); Cleavage: Indistinct; Specific Gravity: 2.63 - 2.75

Formation & Geological History

Formed through the slow crystallization of magma below Earth's surface (intrusive). Most granites date from the Precambrian era to the Cenozoic, commonly forming the core of mountain ranges.

Uses & Applications

Used extensively in construction for countertops, floor tiles, paving stone, curbing, and monuments. High-quality specimens are used in architectural cladding.

Geological Facts

Granite makes up much of the Earth's continental crust. It is one of the hardest and most durable natural stones, which is why it has been used in monuments like Mount Rushmore and the Egyptian pyramids.

Field Identification & Locations

Identify by its interlocking 'salt and pepper' crystalline texture and the presence of visible pink orthoclase feldspar and translucent quartz. Found in massive plutons and mountain belts globally.

Identified on: 4/27/2026

Mode: Standard