mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Cloudy white to opaque
Luster: Vitreous to greasy

Identified April 6, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed from silica-rich hydrothermal solutions or cooling magma in pegmatites. This variety gets its cloudy appearance from microscopic inclusions of fluids trapped during crystal growth.

Uses & applications

Used in glassmaking, ceramics, electronics (as a source of silicon), construction aggregates, and occasionally as decorative landscaping stone or tumbled gemstones.

Geological facts

Milky Quartz is the most common variety of crystalline quartz. Historically, it was used by many indigenous cultures to create sharp stone tools and scrapers.

Field identification & locations

Identify in the field by its hardness (will scratch glass), white milky color, and lack of cleavage. Commonly found in riverbeds, mountain ranges, and within quartz veins of metamorphic or igneous rocks.