mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified July 20, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms from the cooling of hydrothermal veins or as a primary constituent in igneous rocks like granite. It is found across all geological ages, often as one of the last minerals to crystallize from magma.

Uses & applications

Used in glass manufacturing, as an abrasive, in electronics for its piezoelectric properties, and widely in landscaping and as a collector's specimen.

Geological facts

Milky quartz gets its cloudy appearance from minute fluid inclusions of gas and/or liquid trapped during crystal growth. It is the most common variety of crystalline quartz.

Field identification & locations

Identify by its hardness (will scratch glass), lack of cleavage, and characteristic white-cloudy appearance. Commonly found in mountainous regions, riverbeds, and as quartz veins in host rocks.