mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to pale yellow; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Cloudy white to pale yellow
Luster: Vitreous to greasy

Identified July 9, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to pale yellow; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal fluids in veins or as a primary constituent in igneous pegmatites. The milky appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the production of glass, ceramics, and abrasives. Also used as a gemstone in cabochons and as decorative garden stone.

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 and is frequently associated with gold deposits in 'mother lode' style veins.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and translucent white appearance. It is found globally in almost all geological environments, especially in mountain ranges and riverbeds.