mineral

Milky Quartz (Water-Worn Pebble)

Silicon Dioxide (SiO2)

Hardness: 7.0 on Mohs scale; Color: Opaque white to translucent; Luster: Vitreous to waxy (when polished); Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7
Color: Opaque white to translucent
Luster: Vitreous to waxy (when polished)

Identified March 7, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal processes or within igneous pegmatites. This specific specimen’s rounded shape is the result of mechanical weathering and abrasion in a high-energy environment like a riverbed or shoreline.

Uses & applications

Used in the production of glass, ceramics, and abrasives. In construction, it is used as gravel and in concrete. Also used for ornamental stone and occasionally in lower-end jewelry as beads.

Geological facts

Milky Quartz gets its distinctive white color from microscopic fluid inclusions of gas and/or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz found on Earth's crust.

Field identification & locations

Identify in the field by its inability to be scratched by a steel pocket knife and its lack of cleavage planes. Found globally in riverbeds, beaches, and glacial till. Collectors look for pieces with interesting patterns or high translucency.

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