mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Milky white to translucent
Luster: Vitreous to greasy

Identified June 22, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to translucent; 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 fluids. It occurs in a wide variety of geological environments including igneous and metamorphic terrains worldwide.

Uses & applications

Used in glass making, as an abrasive, in the production of silicon metal, as a flux in smelting, and as decorative gravel or gemstone cabochons.

Geological facts

The 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz.

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and white cloudy appearance. Common in riverbeds and mountainous regions. Collectors look for large, well-defined crystal clusters.