mineral

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: white to off-white/cream; Luster: vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: none (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: white to off-white/cream
Luster: vitreous to greasy

Identified June 8, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: white to off-white/cream; Luster: vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: none (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed from silica-rich hydrothermal veins or as a primary constituent in igneous rocks like granite. This specific specimen has been water-worn into a rounded pebble shape over centuries in a river or coastal environment.

Uses & applications

Glass manufacturing, electronics, abrasives, and as decorative stone or landscaping gravel.

Geological facts

Milky quartz gets its cloudy appearance from minute fluid inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and white opaque appearance. Extremely common globally, especially in river beds, beaches, and mountain trails.