mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7.0 on Mohs scale; Color: Cloudly white to opaque; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7
Color: Cloudly white to opaque
Luster: Vitreous (glassy) to greasy

Identified April 8, 2026More mineral →

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Physical properties

Hardness: 7.0 on Mohs scale; Color: Cloudly white to opaque; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed from silica-rich hydrothermal solutions or as a late-stage crystallization in igneous rocks like granites and pegmatites. The white color is caused by tiny liquid or gas inclusions trapped during crystal growth.

Uses & applications

Used in the production of glass, ceramics, and abrasives. In electronics, it is used for its piezoelectric properties. Common in jewelry as beads or cabochons and widely collected by hobbyists.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While often overlooked for clearer varieties like amethyst, large milky quartz veins can contain significant deposits of gold.

Field identification & locations

Identify in the field by its hardness (will scratch glass but not be scratched by a steel knife), lack of cleavage, and characteristic cloudy white Appearance. Found worldwide in nearly every geological environment.