mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Milky white to translucent
Luster: Vitreous/Glassy to waxy

Identified March 7, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky 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 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 over millions of years.

Uses & applications

Used in glass manufacturing, as an abrasive, in the production of silicon chips, and as a common decorative stone or pocket stone for collectors.

Geological facts

Quartz is one of the most abundant minerals in Earth's crust. 'Milky Quartz' specifically gets its name from fluid inclusions that scatter light, creating its signature opaque white look.

Field identification & locations

Identify in the field by its ability to scratch glass and its lack of cleavage (it breaks in irregular, curved 'seashell' shapes). It is commonly found in riverbeds, mountains, and near igneous intrusions worldwide.