mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque; Luster: Vitreous (glassy) to greasy; Crystal structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Cloudy white to opaque
Luster: Vitreous (glassy) to greasy

Identified February 21, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque; Luster: Vitreous (glassy) to greasy; Crystal structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Formation & geological history

Formed through the cooling of magma or precipitation from hydrothermal veins. The 'milky' appearance is caused by microscopic inclusions of fluids or gas trapped during crystal growth. Can be found in rocks from nearly all geological ages.

Uses & applications

Used in glassmaking, abrasives, and as a component in concrete. In jewelry, it is often cut into cabochons or beads. Also used extensively in landscaping and as a collector's specimen for its aesthetic or healing associations.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Historically, it has been used for everything from ancient tools and weapons to modern-day frequency control in electronics due to its piezoelectric properties.

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage (it breaks in irregular, curved shards), and its white 'waxy' appearance. Extremely common in riverbeds, mountains, and as garden gravel worldwide.