mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Identified February 22, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy 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 fluids in veins or as a late-stage mineral in igneous pegmatites. The 'milky' appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the glass and ceramics industry, as an abrasive, in the production of silicon metal for electronics, in landscaping, and as decorative pocket stones for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically is the most common variety of crystalline quartz found in nature. It has been used since prehistoric times for making stone tools when flint was unavailable.

Field identification & locations

Identify in the field by its white color, ability to scratch glass (hardness 7), and lack of cleavage. It is ubiquitous globally, commonly found in mountain ranges, stream beds, and within granite outcrops.