mineral

White Quartz Pebble (with possible Quartz Geode cavity)

Silicon Dioxide (SiO2)

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

Identified March 7, 2026More mineral →

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Physical properties

Hardness: 7 on the 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 silica-rich hydrothermal fluids cooling in veins or cavities within precarious igneous or metamorphic rocks. This specific specimen shows river or beach wear, rounding its edges over thousands of years of erosion.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), construction aggregates, and as decorative stone in landscaping or jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. If the internal cavity contains distinct crystals, it is considered a 'mini geode' or a vug.

Field identification & locations

Identify in the field by its ability to scratch glass and its lack of reaction to acid. Commonly found in riverbeds, beaches, and mountain trails globally. Collectors look for internal druzy crystals in the cavities.

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