mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified July 7, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins and pegmatites when silica-rich fluids cool. The milky appearance is caused by tiny inclusions of liquid or gas trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), and as a landscape stone or decorative rock for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically is one of the most common varieties and can often be found in large, massive quantities known as 'bull quartz.'

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and white waxy appearance. Commonly found in riverbeds, mountains, and gravel pits worldwide.