mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Opaque white to translucent; Luster: Vitreous (glassy) to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Opaque white to translucent
Luster: Vitreous (glassy) to waxy

Identified July 13, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Opaque white to translucent; Luster: Vitreous (glassy) to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed through the crystallization of magma or from hydrothermal veins. The white, milky appearance is caused by tiny inclusions of gas and/or liquid trapped during crystal growth. Can be found in igneous, metamorphic, and sedimentary environments.

Uses & applications

Used in glassmaking, abrasives, and as a gemstone (tumbled stones, beads). Also used in quartz watches and electronics due to piezoelectric properties.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While often overlooked by collectors in favor of clear quartz, it is essential in studying hydrothermal fluid inclusions in geology.

Field identification & locations

Identify by its hardness (scratches glass), waxy luster when tumbled, and lack of cleavage. It is extremely common globally, found in almost every mountainous or riverine environment.