mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Identified March 24, 2026More mineral →

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Physical properties

Hardness: 7 on the 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 through the cooling of silica-rich magma or precipitation from hydrothermal fluids in veins. Milky quartz specifically gets its appearance from microscopic fluid inclusions trapped during crystal growth. Found in various geological ages and environments.

Uses & applications

Used in construction as gravel or aggregate, in the glass-making industry, as a source of silicon for semiconductors, and occasionally in jewelry or lapidary work as cabochons.

Geological facts

Milky quartz is one of the most common minerals on Earth's crust. It is often the primary component of 'Gold Quartz' veins, where it acts as a host rock for gold deposits. Historically, it has been used for stone tools due to its hardness and fracture patterns.

Field identification & locations

Identify in the field by its ability to scratch glass, its milky-white appearance, and lack of cleavage (it breaks in irregular or curved 'conchoidal' surfaces). It is found globally in riverbeds, mountains, and quartz veins within granite. Collectors look for pieces with interesting inclusions or associations with other minerals.