mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness 7 on Mohs scale; white to translucent light grey color; vitreous to greasy luster; trigonal crystal system; conchoidal fracture with no distinct cleavage; specific gravity of 2.65.

Identified July 27, 2026More mineral →

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Physical properties

Hardness 7 on Mohs scale; white to translucent light grey color; vitreous to greasy luster; trigonal crystal system; conchoidal fracture with no distinct cleavage; specific gravity of 2.65.

Formation & geological history

Forms in hydrothermal veins, pegmatites, and igneous rocks during the slow cooling of silica-rich fluids. Found in environments spanning precambrian to recent geological ages.

Uses & applications

Used as an abrasive, in glass manufacturing, electronics (silicon extraction), landscaping, decorative rock, and as an ornamental mineral specimen.

Geological facts

Milky quartz gets its cloudy white appearance from tiny fluid and gas inclusions trapped inside the crystal structure during growth. It is one of the most abundant minerals in the Earth's continental crust.

Field identification & locations

Identified by its scratch-resistance against glass/steel (hardness 7), lack of cleavage, milky color, and irregular conchoidal fracture. Commonly found globally in mountain ranges, gravel beds, and pegmatite deposits.