mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque; Luster: Vitreous to greasy; Crystal structure: Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

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

Identified May 4, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque; Luster: Vitreous to greasy; Crystal structure: Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich hydrothermal fluids in veins or as a late-stage crystallization in igneous rocks like granite. Its milkiness is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glass manufacturing, as an abrasive, in electronics for its piezoelectric properties, and in landscaping or as a gemstone for jewelry and spiritual collecting.

Geological facts

Milky quartz is the most common variety of crystalline quartz. It is often found associated with gold in hydrothermal vein deposits.

Field identification & locations

Identify by its ability to scratch glass, its lack of cleavage, and its characteristic waxy or milky appearance. Frequently found in gravel pits, mountain streams, and quartz veins globally.