mineral

Milky Quartz (Tumbled/Polished)

Silicon Dioxide (SiO2)

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

Identified May 25, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Opaque white to translucent; Luster: Vitreous 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 white color is caused by microscopically small inclusions of fluids (gas or liquid) trapped during crystal growth.

Uses & applications

Used in jewelry (beads, cabochons), decor, glass manufacturing, and electronics due to its piezoelectric properties.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While often overlooked by gem collectors, large high-quality specimens are prized for their spectral purity.

Field identification & locations

Identify by its hardness (will scratch glass), white milky appearance, and lack of cleavage. Tumbled versions are smooth and rounded, commonly found in gravel beds or sold in rock shops.

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