mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White, translucent, or milky; Luster: Vitreous to waxy (when river-worn); Crystal structure: Trigonal/Hexagonal (though rounded here); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: White, translucent, or milky
Luster: Vitreous to waxy (when river-worn)

Identified June 8, 2026More mineral →

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Physical properties

Formation & geological history

Formed from silica-rich hydrothermal fluids or cooling magma. This specific specimen is likely a 'river rock' or 'glacier pebble,' shaped and rounded by mechanical erosion over thousands of years in a high-energy water environment.

Uses & applications

Quartz is used in glassmaking, electronics (piezoelectric properties), abrasives, and as a common decorative stone in landscaping and aquariums.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is known as rock crystal, while the milky appearance of this pebble is caused by tiny fluid inclusions trapped during growth.

Field identification & locations

Identify in the field by its ability to scratch glass and lack of cleavage. It is extremely common globally, found in almost any riverbed or beach. Collectors often look for clear or uniquely colored varieties like amethyst or citrine.