mineral

Milky Quartz Pebble

Crystalline Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to pale cream/tan; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white to pale cream/tan
Luster: Vitreous to waxy

Identified March 3, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to pale cream/tan; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed from hydrothermal veins or cooling of silica-rich magma; this specific specimen has been eroded and smoothed through fluvial or marine water action over thousands of years.

Uses & applications

Used as decorative landscaping stone, in glass manufacturing when crushed, as a source for silicon in electronics, or as minor lapidary material for tumbling.

Geological facts

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

Field identification & locations

Identified by its ability to scratch glass, lack of cleavage, and smooth water-worn texture. Commonly found in riverbeds, beaches, and glacial till worldwide.

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