mineral

Milky Quartz

Crystalline Silicon Dioxide (SiO2)

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

Identified July 19, 2026More mineral →

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Physical properties

Hardness: 7 (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

Quartz forms in a wide variety of environments, most commonly from the cooling of magma or hydrothermal veins. Milky quartz is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, jewelry (as cabochons), semiconductors (when high purity), and as an abrasive in industry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz's white cloudiness is often due to microscopic liquid bubbles that were trapped when the crystal was forming.

Field identification & locations

Identify by its hardness (it will scratch glass), its lack of cleavage, and its characteristic milky-white opacity. It is found globally in almost every geological environment.