mineral

Milky Quartz

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 13, 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 the crystallization of silica-rich hydrothermal solutions or the cooling of silica-saturated magma. The white 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the glassmaking and ceramic industries, as an abrasive, in the production of silicon metal, and in landscaping or as a collector's specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is often found in gold-bearing hydrothermal veins and was historically used by prospectors to locate gold deposits.

Field identification & locations

Identify in the field by its white color, its inability to be scratched by a steel knife (hardness), and the absence of cleavage. It is found globally in igneous, metamorphic, and sedimentary environments.