mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

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

Identified March 22, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed from the crystallization of silica-rich magma or precipitation from hydrothermal fluids in veins. It is found in all geological ages from Precambrian to recent, often in hydrothermal or igneous environments.

Uses & applications

Used in glass manufacturing, electronics (piezoelectric properties), abrasives, and as a decorative stone in landscaping. Lower grade specimens are common in the gemstone industry as 'snow quartz'.

Geological facts

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

Field identification & locations

Identify in the field by its white color, ability to scratch glass (hardness 7), and lack of cleavage (it breaks in irregular, shell-like curves). Common in mountain ranges and stream beds globally.