mineral

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Translucent white to creamy yellow with iron staining. Luster: Vitreous to waxy (when wet or worn). Crystal structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Translucent white to creamy yellow with iron staining
Luster: Vitreous to waxy (when wet or worn)

Identified July 4, 2026More mineral →

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Physical properties

Formation & geological history

Formed from silica-rich hydrothermal veins or cooling magma. This specific specimen has been smoothed and rounded by the action of moving water in a river, stream, or beach environment over thousands of years.

Uses & applications

Common quartz pebbles are used in landscaping, construction aggregate, and as abrasives. High-purity quartz is used in glassmaking and electronics. Tumbled specimens are used in pocket stones or aquarium decor.

Geological facts

Quartz is one of the most abundant minerals in Earth's crust. It is highly resistant to both chemical and physical weathering, which is why it often remains as pebbles long after other minerals have eroded away.

Field identification & locations

Identify by its hardness (it will scratch glass) and lack of cleavage. Look for smooth, rounded shapes in streambeds or coastal areas. This is a very common find for beginning rockhounds.