mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Identified July 25, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Opaque white to off-white; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Forms in hydrothermal veins, pegmatites, igneous intrusive environments, and metamorphic rocks. The white cloudy appearance is caused by tiny gas or liquid bubbles trapped during crystal growth.

Uses & applications

Used in electronics (piezoelectric applications), silicon metal production, glassmaking, construction aggregates, and popular for decorative carving and rock collecting.

Geological facts

Milky Quartz is the most common variety of crystalline quartz found on Earth's surface. Its white appearance is often due to microscopic fluid inclusions dating back billions of years.

Field identification & locations

Identified by its white milky color, inability to be scratched by steel (hardness 7), and glass-like to greasy luster. Widely available worldwide in river beds, gravel pits, and mountain veins.