mineral

Quartz (Water-worn Pebble)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Translucent white to milky with yellow staining. Luster: Vitreous to waxy. Structure: Trigonal. Cleavage: None/Conchoidal fracture. Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Translucent white to milky with yellow staining
Luster: Vitreous to waxy

Identified June 8, 2026More mineral →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 7 on Mohs scale. Color: Translucent white to milky with yellow staining. Luster: Vitreous to waxy. Structure: Trigonal. Cleavage: None/Conchoidal fracture. Specific Gravity: 2.65.

Formation & geological history

Formed from cooling silica-rich magma or hydrothermal veins. This specific specimen has been shaped by fluvial or coastal erosion, resulting in a smooth, tumbled surface over centuries or millennia.

Uses & applications

Quartz is used in glassmaking, electronics, abrasives, and as a semi-precious gemstone. Smooth pebbles like this are often used in landscaping, aquariums, and decorative 'worry stones'.

Geological facts

Quartz is one of the most abundant minerals in Earth's crust. Yellow staining in pebbles like this is usually caused by iron oxide (limonite) impurities during environmental exposure.

Field identification & locations

Identify in the field by its hardness (it will scratch glass) and lack of cleavage. Commonly found in riverbeds, beaches, and glacial deposits worldwide. This specimen is a typical river pebble.