mineral

Rough Quartz (Alluvial Pebbles)

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Colorless to milky white/translucent
Luster: Vitreous (glassy)

Identified February 23, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from cooling magma in pegmatites or hydrothermal veins; these specific specimens are alluvial, meaning they were weathered out and tumbled by water over millions of years.

Uses & applications

Used in glassmaking, electronics (piezoelectric properties), abrasives, as decorative gravel, and for low-cost jewelry or crystal healing practices.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is highly resistant to chemical and physical weathering, which is why it often remains as pebbles while other minerals dissolve.

Field identification & locations

Identify by its ability to scratch glass and its lack of cleavage. Commonly found in riverbeds, beaches, and sedimentary deposits globally. Collectors look for clarity and unique inclusions.

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