Granite (specifically Brown Granite Countertop)

Physical Properties

Hardness: 6-7 on Mohs scale; Color: Mottled brown, black, and tan; Luster: Vitreous (when polished); Crystal structure: Phaneritic (coarse-grained) featuring quartz, feldspar, and biotite mica; Specific gravity: ~2.63 - 2.75.

Formation & Geological History

Formed by the slow crystallization of magma below Earth's surface (intrusive). Most granite is found in continental crust and dates back hundreds of millions to billions of years.

Uses & Applications

Primarily used in residential and commercial construction for countertops, flooring, curbing, and decorative veneers due to its durability and aesthetic appeal.

Geological Facts

Granite is one of the hardest substances in the world, second only to diamonds. The 'speckles' are individual mineral crystals that grew as the magma cooled slowly underground.

Field Identification & Locations

Identify in the field by its interlocking crystalline texture and lack of layering/foliation. Commonly found in large batholiths or mountain ranges. For collectors, it is often gathered as river stones or polished slabs.

Identified on: 4/27/2026

Mode: Standard