mineral

Milky Quartz (Water-worn Pebble)

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale; Color: Opaque white to translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal (Hexagonal system); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on the Mohs scale
Color: Opaque white to translucent
Luster: Vitreous to greasy

Identified March 24, 2026More mineral →

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Physical properties

Formation & geological history

Formed from silica-rich hydrothermal fluids or within igneous pegmatites. This specific specimen has been rounded and polished through alluvial erosion in a river, stream, or beach environment over thousands of years.

Uses & applications

Used industrially in glass manufacturing, as an abrasive, and in electronics (piezoelectric properties). In jewelry, it is often used for beads or cabochons. It is also popular in holistic healing and for decorative landscaping.

Geological facts

Milky quartz gets its white, cloudy appearance from tiny inclusions of gas or liquid trapped during the crystal's formation. It is the most common variety of crystalline quartz found on Earth's crust.

Field identification & locations

Identify in the field by its hardness (it will easily scratch glass but cannot be scratched by a steel knife), white streak, and lack of cleavage. Commonly found in gravel pits, riverbeds, and as veins in metamorphic rocks worldwide.

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Mineral/Rock

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