mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: White/milky, Luster: Vitreous to greasy, Crystal structure: Hexagonal/Trigonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified May 25, 2026More mineral →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 7 (Mohs scale), Color: White/milky, Luster: Vitreous to greasy, Crystal structure: Hexagonal/Trigonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Forms in hydrothermal veins, pegmatites, and as a primary mineral in igneous rocks like granite. The milky appearance is caused by tiny inclusions of liquid or gas trapped during crystal growth.

Uses & applications

Used as a source of silica for glassmaking, abrasive in sandblasting, decorative landscaping, and occasionally as a minor gemstone or for metaphysical collecting.

Geological facts

Milky quartz is the most common variety of crystalline quartz. Its cloudiness is due to microscopic bubbles of water or CO2 that scatter light.

Field identification & locations

Identify by its ability to scratch glass, its lack of cleavage, and its distinctive milky white color. It is ubiquitous globally and often found as rounded river pebbles or milky veins in darker host rocks.