mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 (Mohs scale)
Color: White, opaque to translucent
Luster: Vitreous to greasy

Identified April 30, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins where gas or liquid bubbles are trapped during crystal growth, creating the 'milky' appearance.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), abrasives, ornamental carvings, and low-cost jewelry/tumbled stones.

Geological facts

Milky quartz is the most common variety of crystalline quartz. The white color is caused by tiny fluid inclusions of gas or liquid trapped during the crystal's formation.

Field identification & locations

Identify by its ability to scratch glass and lack of cleavage. It is found globally in pegmatites and hydrothermal veins. Collectors can find it in almost any mountainous or volcanic region.