mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to translucent; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Milky white to translucent
Luster: Vitreous to waxy

Identified June 30, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to translucent; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Formation & geological history

Formed from cooling magma or hydrothermal veins. This specimen is a river-worn pebble, smoothed by water erosion over long periods, likely originating from a larger quartz vein within igneous or metamorphic rock.

Uses & applications

Industrial use in glassmaking, electronics (piezoelectric properties), abrasives, and as decorative landscaping stone or aquarium gravel. Often collected as pocket stones.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its cloudy appearance from tiny inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Identify by its hardness (it can scratch glass), lack of cleavage, and smooth, rounded surface indicating fluvial transport. Found globally in riverbeds, beaches, and glacial deposits.