mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Identified May 25, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins, pegmatites, and as a primary mineral in igneous rocks like granite. The milky appearance is caused by tiny inclusions of gas and liquids trapped during crystal growth.

Uses & applications

Used in glass making, abrasive manufacturing, electronics (due to piezoelectric properties), and as decorative landscaping or collector specimens.

Geological facts

Milky quartz is the most common variety of crystalline quartz. It can sometimes contain microscopic fluid inclusions that give insight into the geological temperature at the time of its formation.

Field identification & locations

Identify in the field by its hardness (scratches glass), lack of cleavage, and white 'cloudy' appearance. Commonly found in mountain ranges and riverbeds globally.