Quartz Pebble

Physical Properties

Hardness: 7 (Mohs scale), Color: tan to milky white with iron staining, Luster: Vitreous to waxy (weathered), Crystal Structure: Trigonal/hexagonal (not visible in pebble form), Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & Geological History

Formed from silica-rich hydrothermal fluids or cooling magma. This specific specimen is a water-worn river pebble or glacial till fragment, likely originating from ancient quartz veins and worn down by erosion over millions of years.

Uses & Applications

Common quartz is used in sandblasting, glassmaking, and electronics. Rounded pebbles are popular for landscaping (river rock) and basic aquarium decor.

Geological Facts

Quartz is the second most abundant mineral in Earth's continental crust. These smooth shapes are formed by 'abrasion'—the process of rocks grinding against each other in water or wind.

Field Identification & Locations

Identify by its hardness (it will scratch glass) and lack of cleavage planes. Found globally in riverbeds, beaches, and glacial deposits. Check for translucency when held to a light.

Identified on: 5/16/2026

Mode: Standard