mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White, cloudy, partially transparent; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: White, cloudy, partially transparent
Luster: Vitreous to greasy

Identified July 6, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White, cloudy, partially transparent; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the cooling and crystallization of silica-rich magma or hydrothermal fluids in veins and pegmatites. The milky appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, as an abrasive, and in the production of silicon transistors. In jewelry, it is often used for beads or ornamental carvings. Large specimens are popular among crystal collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. 'Milky quartz' specifically is the most common variety of crystalline quartz found in nature.

Field identification & locations

Identify in the field by its hardness (will scratch glass easily), lack of cleavage, and white cloudy appearance. It is ubiquitous globally and often found in mountain ranges and riverbeds.