mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to cream; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Opaque white to cream
Luster: Vitreous to greasy

Identified July 15, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Opaque white to cream; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms during the final stages of hydrothermal mineral crystallization in veins or pegmatites; milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glass making, as an abrasive, in the production of silicon chips, and widely as a decorative stone in landscaping or jewelry.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While it lacks the transparency of rock crystal, its cloudy appearance is due to millions of microscopic bubbles trapped inside.

Field identification & locations

Identify in the field by its white color, inability to be scratched by a steel knife, and lack of cleavage planes. Found globally in almost all geological environments.