mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

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

Identified April 3, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal solutions or cooling magma in veins. The white 'milky' color is caused by microscopic inclusions of fluids or gas trapped during crystal growth.

Uses & applications

Used in glass manufacturing, as an abrasive, in electronics (due to piezoelectric properties), construction material, and as a semi-precious gemstone in jewelry and decor.

Geological facts

Milky quartz is the most common variety of crystalline quartz. It can often be found associated with precious metals like gold in hydrothermal vein deposits.

Field identification & locations

Identify by its ability to scratch glass, its lack of cleavage, and its distinctive white, cloudy appearance. It is found globally in almost all geological environments.