mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Identified April 29, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from silica-rich hydrothermal solutions or as a primary constituent of igneous rocks like granite. Its milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), abrasives, and as a popular decorative stone or collector's item in lapidary work.

Geological facts

Milky Quartz is the most common variety of crystalline quartz. It can sometimes contain microscopic pockets of gold, making it a target for prospectors. The white color is due to millions of fluid inclusions called 'vacuoles'.

Field identification & locations

Identified in the field by its hardness (cannot be scratched by steel), lack of cleavage, and white 'cloudy' appearance. It is found globally across all geologic environments, especially in hydrothermal veins.