mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White, opaque to translucent; Luster: Vitreous to waxy when polished; Crystal Structure: Hexagonal (Trigonal); Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: White, opaque to translucent
Luster: Vitreous to waxy when polished

Identified May 13, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal fluids in veins or as a late-stage mineral in igneous pegmatites. The white color is caused by minute fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, as an abrasive, in electronics (piezoelectric properties), and frequently as decorative garden stones, tumbled pocket stones, or in costume jewelry.

Geological facts

Milky quartz is the most common variety of crystalline quartz. It is often found in large veins that can be hundreds of feet long, frequently hosting gold in hydrothermal deposits.

Field identification & locations

Identify in the field by its hardness (scratches glass), lack of cleavage, and typical white, 'cloudy' appearance. It is found globally, particularly in mountainous regions and riverbeds as rounded pebbles.