Quartz Pebble (often referred to as 'Sea Glass' or 'River Stone' when worn smooth)

Physical Properties

Hardness: 7 (Mohs scale), Color: Pinkish-white/milky, Luster: Vitreous/waxy, Crystal structure: Trigonal (often crypto-crystalline in smoothed specimens), Cleavage: None/Conchoidal fracture

Formation & Geological History

Formed from silica-rich fluids in igneous or metamorphic environments. This specific specimen has been chemically or mechanically weathered and rounded by water action over geological time.

Uses & Applications

Used in landscaping, as tumbling rough for hobbyists, or as a source of silica for glass manufacturing if found in bulk.

Geological Facts

Quartz is the second most abundant mineral in the Earth's continental crust. Its extreme resistance to chemical and physical weathering is why it is the primary component of beach sand.

Field Identification & Locations

Identify by its hardness (it can scratch glass and steel) and lack of cleavage. Common in riverbeds and on beaches worldwide.

Identified on: 4/19/2026

Mode: Standard