mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: White to translucent, Luster: Vitreous to greasy, Crystal structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified June 16, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: White to translucent, 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 late-stage mineral in igneous pegmatites. It can be found in a wide variety of geological environments ranging from Precambrian to recent ages.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), abrasives, and as a decorative stone in landscaping and jewelry. It is also a primary source of high-purity silicon.

Geological facts

The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz found on Earth.

Field identification & locations

Identified in the field by its white color, inability to be scratched by a steel knife, and lacks cleavage. Commonly found in riverbeds, mountains, and near volcanic regions globally.