Granite

Physical Properties

Hardness: 6-7 on Mohs scale; Color: Salt-and-pepper (white, pink, gray, and black); Luster: Vitreous to dull; Crystal structure: Phaneritic (coarse-grained, visible crystals); Specific gravity: 2.63 to 2.75.

Formation & Geological History

Formed from the slow crystallization of magma below Earth's surface. It is the primary component of continental crust, often dating from the Precambrian to Cenozoic eras.

Uses & Applications

Extensively used in construction for countertops, floor tiles, paving stones, monuments, and as crushed stone for road base and concrete aggregate.

Geological Facts

Granite is one of the hardest substances in the world, second only to diamonds. Famous landmarks like Mount Rushmore and the base of the Statue of Liberty are made of granite.

Field Identification & Locations

Identify in the field by its grainy, speckled texture and visible interlocking crystals of quartz, feldspar, and mica. It is found globally in mountainous regions and continental shields.

Identified on: 4/29/2026

Mode: Standard