mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale; Color: Opaque white (due to fluid inclusions); Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on the Mohs scale
Color: Opaque white (due to fluid inclusions)
Luster: Vitreous to greasy

Identified March 22, 2026More mineral →

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Physical properties

Formation & geological history

Forms in nearly all geological environments but most commonly in hydrothermal veins and pegmatites through the cooling of silica-rich magma or hot aqueous solutions. Specimens can range from prehistoric to very recent formations.

Uses & applications

Used industrially as an abrasive, in the production of glass and ceramics, as a source for silicon metal for electronics, and in landscaping or construction. It is also common in metaphysical jewelry and beginner rock collections.

Geological facts

Milky quartz gets its cloudy appearance from tiny microscopic bubbles of liquid or gas trapped during the crystal's growth. It is the most common variety of crystalline quartz found on Earth's crust.

Field identification & locations

Identify in the field by its white color, ability to scratch glass (hardness 7), and unique conchoidal (shell-like) fracture pattern. It is commonly found in gravel pits, mountains, and stream beds globally. Collectors look for pieces with large crystal faces or inclusions of other minerals like gold or pyrite.