Quartz Pebble

Physical Properties

Hardness: 7 (Mohs scale), Color: White/Translucent, Luster: Vitreous to greasy, Crystal structure: Trigonal/Hexagonal (though rounded here), Cleavage: None (conchoidal fracture), Specific gravity: 2.65

Formation & Geological History

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

Uses & Applications

Common quartz is used in glassmaking, abrasives, and as a concrete aggregate. Small rounded pebbles are frequently used in decorative landscaping and aquarium substrata.

Geological Facts

Quartz is the second most abundant mineral in Earth's continental crust. It is chemically very stable, which is why it often remains as pebbles long after the host rock has weathered away.

Field Identification & Locations

Identify in the field by its hardness (it can scratch glass) and lack of cleavage. It is found globally in almost all geological environments, particularly in beach and river deposits.

Identified on: 4/21/2026

Mode: Standard