mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to pale yellow; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Cloudy white to pale yellow
Luster: Vitreous to greasy

Identified July 11, 2026More mineral →

Explore Milky Quartz in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to pale yellow; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

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

Uses & applications

Used in glassmaking, as an abrasive, in electronics (piezoelectric properties), as decorative gravel, and as a source of silicon metal.

Geological facts

Quartz is one of the most abundant minerals in Earth's crust. Milky quartz specifically gets its color from tiny fluid inclusions that scatter light, similar to how water droplets create fog.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and translucent 'milky' appearance. Found worldwide in nearly every geological environment.