mineral

Milky 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 May 3, 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 silica-rich magma or from hydrothermal veins where hot water deposits silicon and oxygen into cracks. Found globally in all geological environments.

Uses & applications

Used in glassmaking, abrasives, electronic oscillators (piezoelectric properties), jewelry, and as a decorative stone in landscaping.

Geological facts

Milky quartz gets its characteristic white cloudiness from tiny inclusions of gas or liquid trapped during the crystal's formation over millions of years.

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and white color. Very common in igneous terrain and stream beds. Common in North America, Brazil, and Madagascar.