mineral

Milky Quartz

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale), Color: White/Opaque, Luster: Vitreous to Greasy, Crystal Structure: Trigonal/Hexagonal, Cleavage: Indistinct/Conchoidal Fracture, Specific Gravity: 2.65

Identified July 1, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: White/Opaque, Luster: Vitreous to Greasy, Crystal Structure: Trigonal/Hexagonal, Cleavage: Indistinct/Conchoidal Fracture, Specific Gravity: 2.65

Formation & geological history

Formed during the final stages of hydrothermal crystallization in igneous veins or metamorphic environments. The milky appearance is caused by tiny fluid inclusions of gas and/or liquid trapped during crystal growth.

Uses & applications

Used in glass manufacturing, electronics (piezoelectric properties), abrasives, as a flux in metallurgy, and widely used in landscaping and as a decorative collector stone.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While it lacks the transparency of rock crystal, the millions of microscopic bubbles trapped inside hold a geological record of the fluids present during its formation.

Field identification & locations

Identify by its white opaque color, lack of cleavage (breaks like glass), and its ability to scratch glass. Commonly found in river beds, beaches, and mountain outcrops globally.