mineral

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

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

Hardness: 7 on Mohs scale
Color: White to translucent gray
Luster: Vitreous (glassy) to greasy

Identified March 22, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. Milky quartz particularly gets its cloudy appearance from microscopic inclusions of fluids or gas trapped during crystal growth. It is found in geological environments ranging from Precambrian to Holocene.

Uses & applications

Used in the production of glass, ceramics, and abrasives. In construction, it is used as a decorative aggregate. High-quality specimens are used in electronics for their piezoelectric properties, while rough pieces are popular for starting rock collections.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. 'Milky' quartz is often associated with gold deposits in 'mother lode' veins. It is chemically very stable and resistant to weathering.

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage (it breaks in irregular, shell-like curves), and its white, opaque color. It is extremely common worldwide, especially in mountainous regions and stream beds.