mineral

Milky Quartz

Crystalline Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Cloudy white to opaque
Luster: Vitreous to greasy

Identified April 6, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); 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 occurs in a wide variety of geological environments ranging from igneous to metamorphic settings across all geological ages.

Uses & applications

Used as an abrasive, in glass manufacturing, as a source for silicon, in construction as decorative stone/gravel, and occasionally as a low-cost gemstone or healing crystal in the metaphysical community.

Geological facts

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

Field identification & locations

Identify in the field by its hardness (scratches glass), lack of cleavage, and characteristic greasy luster on fractured surfaces. It is found globally, particularly in mountainous regions and riverbeds.