mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: cloudy white to translucent gray, Luster: vitreous to greasy, Crystal structure: Trigonal/Hexagonal, Cleavage: poor (conchoidal fracture), Specific Gravity: 2.65

Identified May 24, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: cloudy white to translucent gray, Luster: vitreous to greasy, Crystal structure: Trigonal/Hexagonal, Cleavage: poor (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed through hydrothermal processes where silica-rich fluids cool in veins or pegmatites; found in igneous, metamorphic, and sedimentary environments across all geological ages

Uses & applications

Used in glass manufacturing, optics, abrasives, as an aggregate in construction, and as decorative gravel; frequently collected by mineral enthusiasts

Geological facts

Milky quartz gets its characteristic phantom appearance from microscopic fluid inclusions of gas or liquid trapped during crystal growth. It is the most common variety of crystalline quartz on Earth.

Field identification & locations

Identify by its hardness (scratches glass), white color, and lack of distinct cleavage. Common in mountain ranges and riverbeds globally; often serves as a 'host rock' for gold veins.