mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White to milky translucent; Luster: Vitreous to waxy (especially when smoothed); Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: White to milky translucent
Luster: Vitreous to waxy (especially when smoothed)

Identified June 25, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the crystallization of silica-rich magma or precipitation from hydrothermal veins. This specific specimen is a 'river rock' or 'beach pebble,' shaped and polished by the mechanical weathering and transport in water over hundreds to thousands of years.

Uses & applications

Used in manufacturing of glass, abrasives, and electronics. Smooth pebbles are popular in landscaping, aquarium decor, and as 'worry stones' for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. When found in riverbeds, its extreme hardness allows it to survive long-distance transport while softer minerals break down into silt.

Field identification & locations

Identify in the field by its ability to scratch glass and its lack of cleavage. It is commonly found in riverbeds, beaches, and glacial deposits worldwide. Collectors look for unique shapes or clarity.