mineral

Milky Quartz

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale. Color: Milky white to semi-translucent. Luster: Vitreous to greasy when polished. Crystal Structure: Hexagonal/Trigonal. Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Milky white to semi-translucent
Luster: Vitreous to greasy when polished

Identified July 26, 2026More mineral →

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Physical properties

Formation & geological history

Forms in hydrothermal veins, pegmatites, and igneous rocks through the cooling and crystallization of silica-rich fluids. Milky appearance is caused by microscopic fluid inclusions trapped during growth.

Uses & applications

Used extensively as decorative landscape stone, in aquariums, polished as tumbled stones, for jewelry, and historically as a source of silicon for glassmaking and electronics.

Geological facts

The distinctive milky white appearance is due to millions of tiny gas or liquid bubbles trapped within the quartz crystal structure as it formed millions of years ago.

Field identification & locations

Identified by its white, cloudy appearance, hardness (scratches glass, cannot be scratched by a steel knife), and lack of cleavage. Extensively found in gravel pits, riverbeds, and quartz veins worldwide.