Granite

Physical Properties

Hardness: 6-7 Mohs; Color: Salt and pepper appearance with pink, white, and grey; Luster: Dull to vitreous; Structure: Phaneritic (coarse-grained) crystalline texture; Cleavage: None (though feldspars show cleavage).

Formation & Geological History

Formed from the slow subterranean cooling of silica-rich magma (plutonic). Typically formed in continental crust during mountain-building events (orogenies) over millions of years.

Uses & Applications

Extensively used in construction for countertops, floor tiles, paving stones, curbing, and as aggregate. Also used for monuments and sculptures due to its durability.

Geological Facts

Granite is the primary rock composing the Earth's continental crust. It is one of the hardest and most durable substances on Earth, which is why it has been used since ancient Egypt for obelisks and pyramids.

Field Identification & Locations

Identify by its visible interlocking crystals of quartz (clear/grey), feldspar (white/pink), and dark minerals like mica or hornblende. Commonly found in mountain ranges and glaciated regions as erratic boulders.

Identified on: 4/30/2026

Mode: Standard