mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Opaque white to translucent
Luster: Vitreous to greasy

Identified July 21, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; 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 of igneous rocks like granite. The milky appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glass manufacturing, as a source of silicon for electronics, in construction as aggregate, for landscaping, and as decorative carvings or tumbled stones.

Geological facts

Milky Quartz is the most common variety of crystalline quartz. While it lacks the clarity of Rock Crystal, it is chemically identical and can form massive veins that span miles.

Field identification & locations

Identify by its hardness (will scratch glass), white color, and lack of cleavage planes. Found globally, especially in pegmatites and metamorphic belts. Collectors look for well-defined crystal terminations.