mineral

Milky Quartz (Tumbled Pebble)

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale; Color: Opaque white to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Opaque white to translucent
Luster: Vitreous to greasy

Identified March 26, 2026More mineral →

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Physical properties

Hardness: 7 on the Mohs scale; Color: Opaque white to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal solutions or cooling magma in veins and pegmatites. The 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. They are found in all geological ages.

Uses & applications

Used widely in decorative landscaping, jewelry (as cabochons or tumbled stones), glass manufacturing, and as 'pocket stones' in the metaphysical community.

Geological facts

Milky quartz is one of the most common minerals on Earth's crust. It is often found as the 'vein' material that contains gold in hydrothermal deposits. Legend has it that the white color comes from the inclusion of clouds.

Field identification & locations

Identify in the field by its hardness (it will easily scratch glass) and lack of cleavage. It is commonly found in riverbeds, beaches, and mountain trails globally. For collectors, look for pieces with few surface fractures.

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