mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Identified June 8, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of magma or hydrothermal activity. The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth. Found in various geological ages and environments, particularly in igneous veins and metamorphic rocks.

Uses & applications

Used as an abrasive in industry, in the production of glass and ceramics, as a landscaping material, and for decorative carvings or jewelry specimens.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While often overlooked for clearer varieties like rock crystal, massive beds of milky quartz can span entire mountain ranges.

Field identification & locations

Identify in the field by its distinct white color, inability to be scratched by a steel pocket knife, and lack of cleavage (it breaks in irregular, shell-like curves). It is ubiquitous worldwide, especially in gravel pits and mountain veins.