mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 (Mohs scale)
Color: Opaque white to milky gray
Luster: Vitreous to greasy

Identified June 7, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins and pegmatites through the cooling of silica-rich solutions. It is found in geological settings ranging from Precambrian to recent ages.

Uses & applications

Used in glass making, abrasives, silicon production, electronics (due to piezoelectric properties), and as decorative landscaping stone.

Geological facts

Milky quartz gets its cloudy appearance from tiny fluid inclusions of gas or liquid trapped during crystal growth. It is the most common variety of crystalline quartz found on Earth.

Field identification & locations

Identify by its hardness (scratches glass), white color, and lack of cleavage. Commonly found in mountain regions, riverbeds, and as gravel. Collectors look for pieces with interesting surface textures or associated minerals.