mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 mohs; Color: Opaque white to cream; Luster: Vitreous to greasy; Crystal Structure: Hexagonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 mohs
Color: Opaque white to cream
Luster: Vitreous to greasy

Identified June 1, 2026More mineral →

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Physical properties

Hardness: 7 mohs; Color: Opaque white to cream; Luster: Vitreous to greasy; Crystal Structure: Hexagonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Forms in hydrothermal veins or pegmatites from cooling silica-rich fluids. It is often ancient, ranging from millions to billions of years old, and is one of the most common crustal minerals.

Uses & applications

Used in glassmaking, as an abrasive, in concrete as aggregate, as a source for silicon chips, and as decorative stone or landscaping mulch.

Geological facts

The milky white color is caused by tiny inclusions of gas and/or liquid trapped during crystal growth. It is the most common variety of crystalline quartz.

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and white opaque appearance. Look for it in riverbeds, mountain outcrops, and road cuts.