mineral

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Hardness: 7 Mohs; Color: White to off-white, translucent to opaque; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 Mohs
Color: White to off-white, translucent to opaque
Luster: Vitreous to greasy

Identified March 4, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: White to off-white, translucent to opaque; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal solutions or cooling of magma. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. It is found in igneous, metamorphic, and sedimentary environments worldwide across all geological ages.

Uses & applications

Used in glassmaking, construction as decorative stone/aggregate, abrasives, and as a source for silicon in electronics. In jewelry, it is often tumbled or cut into cabochons. It is also a very common collector mineral for beginners.

Geological facts

Milky quartz is the most common variety of crystalline quartz. It can sometimes contain minute amounts of gold in hydrothermal veins, leading prospectors to use it as an indicator mineral. It displays piezoelectricity, meaning it generates an electric charge when mechanical stress is applied.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), lack of cleavage, and white waxy appearance. It is found globally in pegmatites, hydrothermal veins, and as river pebbles. Collectors should look for unique crystalline shapes or associations with other minerals.