mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White to translucent cloudy; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65.

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

Identified March 31, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to translucent cloudy; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed from the crystallization of silica-rich hydrothermal fluids in veins or as a primary constituent in igneous rocks like granite. It is abundantly found in formations ranging from the Precambrian to recent times.

Uses & applications

Used in the manufacturing of glass and ceramics, as an abrasive in sandblasting, in construction as aggregate, and frequently in lapidary work for tumbled stones and decorative carvings.

Geological facts

Milky quartz gets its distinctive white, cloudy appearance from tiny microscopic 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 hardness (cannot be scratched by a steel knife) and its white, opaque-to-translucent color. Commonly found in riverbeds and mountainous regions. Collectors look for pieces with interesting patterns or embedded minerals.