Granite / Quartz Vein Rock

Physical Properties

Hardness: 6-7 Mohs; Color: Grey, white, and black mottled; Luster: Vitreous to dull; Crystal structure: Phaneritic (visible crystals); Cleavage: Poor/none.

Formation & Geological History

Formed through the slow cooling of silica-rich magma deep underground. Quartz veins often form later when hydrothermal fluids fill fractures in the cooling rock.

Uses & Applications

Commonly used in construction, countertops, road base, and as decorative landscaping stone.

Geological Facts

Granite makes up a large portion of the Earth's continental crust. These specific pieces show hydrothermal quartz associated with darker mafic minerals.

Field Identification & Locations

Identify by its 'salt and pepper' appearance and hardness (it will scratch glass). Often found in mountain ranges or glacial till.

Identified on: 4/26/2026

Mode: Standard