mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to translucent tan/brown; Luster: Vitreous to waxy (when polished by water); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white to translucent tan/brown
Luster: Vitreous to waxy (when polished by water)

Identified March 18, 2026More mineral →

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Physical properties

Formation & geological history

Formed from cooling magma or hydrothermal veins. These specific rounded specimens are the result of weathering and fluvial (river) erosion, where water transport tumbles the mineral into a smooth, oval shape over thousands of years.

Uses & applications

Used primarily in construction (aggregate), glassmaking, and as an abrasive. In smaller, polished forms, they are used for decorative landscaping, aquariums, and occasionally tumbled jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is chemically very stable, which is why quartz pebbles often remain long after other minerals in a rock have weathered away.

Field identification & locations

Identify in the field by its hardness (it will scratch glass) and lack of cleavage. It is commonly found in riverbeds, beaches, and glacial till. For collectors, look for high clarity or unique internal inclusions.