mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Identified March 17, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through crystallization of silica-rich magma or precipitation from hydrothermal veins. It is found in a vast range of geological ages from Precambrian to recent, often occurring in igneous intrusions and metamorphic environments.

Uses & applications

Used extensively in the glassmaking and foundry industries, as an abrasive, in the production of silicon chips for electronics, and as decorative gravel or landscaping stone.

Geological facts

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

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage, and its waxy or vitreous luster. It is commonly found in gravel pits, riverbeds, and as veins in larger rock outcrops. Collectors should look for distinct crystal faces, though it often appears as rounded pebbles.