mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque; Luster: Vitreous (glassy) 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 (glassy) to greasy

Identified March 16, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque; Luster: Vitreous (glassy) 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. The white 'milky' appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth. Can be found in all geological ages.

Uses & applications

Used in the manufacturing of glass and ceramics, as an abrasive, in the production of silicon for electronics, and as decorative stone or landscaping gravel.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is often the variety of quartz found in gold-bearing hydrothermal veins, making it a 'pathfinder' for prospectors.

Field identification & locations

Identify in the field by its hardness (it can scratch glass), lack of cleavage, and translucent-to-opaque white color. It is commonly found in riverbeds, mountains, and as veins in larger rock outcrops globally.