sedimentary

Quartz Pebble

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness of 7 on the Mohs scale, white or translucent color, vitreous to greasy luster, hexagonal crystal system when well-formed, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Identified August 4, 2026More sedimentary →

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Physical properties

Hardness of 7 on the Mohs scale, white or translucent color, vitreous to greasy luster, hexagonal crystal system when well-formed, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Formation & geological history

Formed through the mechanical and chemical weathering of parent rocks containing quartz (such as granite or pegmatite). Over millions of years, water transport in rivers or ocean waves rounds the fragments into smooth pebbles.

Uses & applications

Used in landscaping, decorative gravel, abrasive manufacturing, and sometimes tumbling for jewelry or lapidary crafts.

Geological facts

Quartz is one of the most abundant and durable minerals in Earth's continental crust, making it very resistant to weathering which allows pebble forms to survive intact over immense geological timescales.

Field identification & locations

Found worldwide in riverbeds, beaches, and alluvial deposits. Easily identified in the field by its high hardness (scratches glass), lack of reaction to acid, and smooth water-worn shape.