mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Identified June 18, 2026More mineral →

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Physical properties

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

Formation & geological history

Commonly forms in hydrothermal veins, pegmatites, and as a primary constituent in igneous rocks like granite. Its milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the production of glass, ceramics, and abrasives. In electronics, it is used for its piezoelectric properties. Medium-quality stones are used for landscaping or as decorative garden stones.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically gets its color from microscopic bubbles of water and air that reflect light in all directions.

Field identification & locations

Identify in the field by its hardness (it will easily scratch glass), its white waxy appearance, and the lack of cleavage or reaction to acid. It is found globally in almost all geological environments.