mineral

Milky Quartz

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 14, 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 crystallization of silica-rich hydrothermal solutions or the cooling of magma in igneous veins. The milky appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the manufacturing of glass and ceramics, as an abrasive in sandpaper, in the production of silicon for electronics, and as a popular decorative stone for landscaping and jewelry (cabochons).

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky Quartz specifically contains millions of tiny 'bubbles' that scatter light, creating its signature white color, rather than being clear like Rock Crystal.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife (hardness 7) and its lack of cleavage. It is extremely common worldwide, particularly in pegmatites and hydrothermal veins. Collectors should look for unique crystal shapes or associations with other minerals.