mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 (Mohs scale)
Color: White, translucent to opaque
Luster: Vitreous to greasy

Identified May 9, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White, translucent to opaque; Luster: Vitreous to greasy; Crystal Structure: 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 fluid or gas inclusions trapped during crystal growth. Can be millions to billions of years old.

Uses & applications

Used in the production of glass, ceramics, and abrasives. Also used in electronics for its piezoelectric properties and in landscaping or as a low-cost gemstone/collector specimen.

Geological facts

Milky quartz is the most common variety of crystalline quartz. Historically, it was used by many cultures to create tools and weapons due to its hardness and ability to fracture into sharp edges.

Field identification & locations

Identify by its ability to scratch glass and its lack of cleavage. It is found globally in igneous, metamorphic, and sedimentary environments. Often found as rounded pebbles in stream beds.