mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Identified May 9, 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/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed from the cooling of magma or by precipitation from hydrothermal veins. The cloudiness is caused by minute fluid inclusions of gas or liquid trapped during crystal growth. Can be found in geological environments ranging from billions of years old to relatively recent deposits.

Uses & applications

Used primarily as decorative stone, in landscaping, as a source of silica for glassmaking, and in metaphysical collecting. Larger, clearer specimens are used in jewelry as cabochons.

Geological facts

Milky quartz is the most common variety of crystalline quartz. The white color is often due to microscopic inclusions of fluids that have been trapped since the time the crystal first grem.

Field identification & locations

Identify in the field by its white color, its inability to be scratched by a steel knife (hardness 7), and its lack of cleavage. It is found globally in pegmatites, hydrothermal veins, and as pebbles in riverbeds or beaches.