Granite

Physical Properties

Hardness: 6-7 Mohs; Color: Pink, white, gray, and black mottled patterns; Luster: Dull to vitreous; Crystal Structure: Phaneritic (coarse-grained); Specific Gravity: 2.63 to 2.75.

Formation & Geological History

Formed from the slow crystallization of magma below Earth's surface. It is a major component of the continental crust and can range in age from millions to billions of years old.

Uses & Applications

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

Geological Facts

Granite is one of the hardest and most durable substances on Earth, making it a favorite for lasting monuments. It contains quartz, feldspar, and mica, which give it its characteristic sparkle.

Field Identification & Locations

Identify in the field by its interlocking coarse grains and speckled multi-color appearance. It is commonly found in mountain ranges and eroded shield areas like the Appalachians or the Canadian Shield.

Identified on: 4/20/2026

Mode: Standard