mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale; Color: Opaque white to translucent grey; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on the Mohs scale
Color: Opaque white to translucent grey
Luster: Vitreous (glassy) to greasy

Identified March 21, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. They can range from Precambrian to recent geological ages.

Uses & applications

Used in the gemstone industry as tumbled stones or cabochons, as an abrasive in sandpaper, in the manufacturing of glass and ceramics, and valued by collectors for spiritual or decorative purposes.

Geological facts

Milky quartz is the most common variety of crystalline quartz. It often appears in large massive forms rather than individual crystals. Historically, it has been used for making stone tools and in various cultures as a symbol of purity.

Field identification & locations

Identify in the field by its white/translucent appearance and the fact that it can easily scratch glass but cannot be scratched by a steel knife. Commonly found in quartz veins, pegmatites, and as river pebbles.