mineral

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to translucent yellowish; Luster: Vitreous to waxy (especially when water-worn); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white to translucent yellowish
Luster: Vitreous to waxy (especially when water-worn)

Identified June 23, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins or as a primary constituent in igneous rocks like granite. This specific specimen is a water-worn river pebble, shaped by erosion and transport in high-energy aqueous environments over thousands of years.

Uses & applications

Industrial uses include glassmaking, abrasives, and electronics. Small pebbles are commonly used for decorative landscaping, aquarium gravel, or as tumbled pocket stones.

Geological facts

The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during the crystal's formation. Quartz is the second most abundant mineral in Earth's continental crust.

Field identification & locations

Identify in the field by its hardness (it will scratch glass) and lack of cleavage. Commonly found in riverbeds, beaches, and glacial deposits worldwide. Collectors often look for pieces with interesting mineralization or unique erosion patterns.