mineral

Milky Quartz

Silicon Dioxide (SiO2)

Mohs hardness: 7. Color: Milky white to translucent. Luster: Vitreous to greasy. Crystal structure: Trigonal/Hexagonal. Cleavage: Indistinct/Conchoidal fracture. Specific gravity: 2.65.

Hardness: 7
Color: Milky white to translucent
Luster: Vitreous to greasy

Identified July 1, 2026More mineral →

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Physical properties

Mohs hardness: 7. Color: Milky white to translucent. Luster: Vitreous to greasy. Crystal structure: Trigonal/Hexagonal. Cleavage: Indistinct/Conchoidal fracture. Specific gravity: 2.65.

Formation & geological history

Forms in hydrothermal veins, pegmatites, and igneous rocks through the cooling of silica-rich solutions. Often found as water-worn pebbles in stream beds and beaches.

Uses & applications

Used in glass making, electronics (piezoelectric properties), abrasives, construction aggregates, and as ornamental stone or landscaping rock.

Geological facts

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

Field identification & locations

Identify by its hardness (scratches glass), white color, and lack of cleavage. Look for it in gravel pits, mountain streams, and quartz veins in bedrock.