mineral

Milky Quartz (Crystal Cluster)

Silicon Dioxide (SiO2) - Quartz Variety

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque; Luster: Vitreous (glassy) to greasy; Crystal Structure: Hexagonal (Trigonal); Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65

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

Identified March 18, 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 (Trigonal); Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through hydrothermal processes where silica-rich fluids cool in veins or cavities within igneous, metamorphic, or sedimentary rocks. The milky appearance is caused by tiny inclusions of liquid, gas, or both, trapped during crystal growth over millions of years.

Uses & applications

Commonly used as decorative specimens, in metaphysical healing practices, as a source for high-purity silica in glass making, and as an abrasive in industrial applications.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While it lacks the clarity of 'Rock Crystal,' high-quality clusters with distinct points like this one are highly prized by collectors for their geometric beauty.

Field identification & locations

Identify in the field by its distinct hexagonal crystal points (six-sided prisms) and its inability to be scratched by a steel knife. Commonly found in pegmatites and hydrothermal veins worldwide, notably in Arkansas (USA), Brazil, and the Alps.

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