Granite

Physical Properties

Hardness: 6-7 on Mohs scale; Color: typically pink, gray, or white with dark specks; Luster: Vitreous to dull; Crystal structure: Phaneritic (coarse-grained texture); Cleavage: Granitoid rocks do not have a uniform cleavage but minerals within like mica and feldspar do.

Formation & Geological History

Formed from the slow crystallization of magma below Earth's surface. Found in continental crust, often appearing in intrusive bodies like batholiths. Ages can range from Precambrian to Cenozoic.

Uses & Applications

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

Geological Facts

Granite is the most common igneous rock found on Earth's continents. The iconic peaks of Yosemite National Park are made of granite.

Field Identification & Locations

Identify in the field by its visible interlocking crystals of quartz (clear/gray), feldspar (white/pink), and mica (black/shiny). Common in mountain ranges and eroded continental shields.

Identified on: 4/23/2026

Mode: Standard