Quartz Pebble

Physical Properties

Hardness: 7 (Mohs scale), Color: White to Milky, Luster: Vitreous/Waxy, Crystal Structure: Hexagonal (trigonal), Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & Geological History

Formed from cooling silica-rich magma or precipitation in hydrothermal veins. This specific specimen has been chemically and physically weathered and rounded by water action in a river or coastal environment.

Uses & Applications

Commonly used in glassmaking, electronics (piezoelectric properties), abrasives, and as decorative river stone in landscaping.

Geological Facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is clear, but the milky white color seen here is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Field Identification & Locations

Identify by its hardness (it will scratch glass) and lack of cleavage. Commonly found in riverbeds, beaches, and mountain trails worldwide.

Identified on: 4/26/2026

Mode: Standard