mineral

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to opaque white; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal (though usually massive in pebbles); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white to opaque white
Luster: Vitreous to greasy

Identified June 25, 2026More mineral →

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Physical properties

Formation & geological history

Formed primarily from hydrothermal veins or as a component of igneous rocks like granite. The 'milky' appearance is caused by microscopic inclusions of gas or liquid trapped during crystal growth. This specific specimen has been rounded by fluvial (water) erosion over thousands of years.

Uses & applications

Used in glassmaking, abrasives, and electronics. Common milky quartz is also used for landscaping, as a decorative stone, and in metaphysical collections.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its white color from fluid inclusions that were trapped while the crystal was forming.

Field identification & locations

Identify in the field by its hardness (it can scratch glass), its white color, and its waxy or greasy luster when wet or polished. Commonly found in riverbeds, beaches, and mountain trails worldwide.