mineral

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

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

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

Identified March 5, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed via cooling of silica-rich magma or from hydrothermal veins. This specimen is water-worn, smoothed over thousands of years in a high-energy environment like a riverbed or shoreline. Its geological age varies by location, often millions of years old.

Uses & applications

Industrial uses include glass manufacturing and electronics as a source of high-purity silica. Commonly used as a decorative substrate in aquariums and landscaping, or as a pocket stone for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'quarz', which means 'hard'. Milky quartz gets its cloudy appearance from tiny fluid inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and smooth, rounded water-worn texture. It is ubiquitous in riverbeds, beaches, and glacial deposits worldwide. Collectors value specimens with high translucency or unique inclusions.