Granite

Physical Properties

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

Formation & Geological History

Formed through the slow crystallization of magma below Earth's surface in continental crust environments. Granite cooling can take millions of years, allowing large crystals to grow. It is typically Found in batholiths and mountain ranges.

Uses & Applications

Extensively used in construction for countertops, floor tiles, paving stones, monuments, and as aggregate in roads and infrastructure.

Geological Facts

Granite is the most common igneous rock found on Earth's continental crust. Its name comes from the Latin 'granum', meaning a grain, in reference to its coarse-grained structure.

Field Identification & Locations

Identify by its interlocking 'mosaic' of visible crystals, primarily clear/white quartz, milky feldspar, and black biotite or hornblende. It is very hard and will scratch glass easily.

Identified on: 4/17/2026

Mode: Standard