Rock Identifier
Quartz Pebble (Silicon Dioxide (SiO2)) — sedimentary
sedimentary

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale, Color: Brownish to amber, Luster: Vitreous to waxy due to abrasion, Crystal structure: Trigonal (microcrystalline or massive in this weathered form), Cleavage: None, Specific Gravity: 2.65

Identified More sedimentary
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Physical properties

Hardness: 7 on the Mohs scale, Color: Brownish to amber, Luster: Vitreous to waxy due to abrasion, Crystal structure: Trigonal (microcrystalline or massive in this weathered form), Cleavage: None, Specific Gravity: 2.65

Formation & geological history

Formed through the mechanical weathering and water transport of parent igneous or metamorphic rocks containing quartz veins. Over thousands to millions of years, wave action or river currents smooth and round the grain into a pebble.

Uses & applications

Used in landscaping, decorative stone, aquarium gravel, and as a natural specimen for amateur rock collectors.

Geological facts

Quartz is one of the most abundant and durable minerals in Earth's continental crust. Its high hardness and resistance to chemical weathering allow it to survive long transport journeys where other minerals erode away.

Field identification & locations

Found globally in riverbeds, beaches, and ancient sedimentary conglomerates. Easily identified by its high hardness (scratches glass) and smooth, water-worn shape.