mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 Mohs scale; Color: Opaque white to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 Mohs scale
Color: Opaque white to translucent
Luster: Vitreous to greasy

Identified April 30, 2026More mineral →

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Physical properties

Hardness: 7 Mohs scale; Color: Opaque white to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins and pegmatites when silica-rich fluids cool. The white color is caused by tiny fluid inclusions of gas and/or liquid trapped during crystal growth. Found in various geological ages worldwide.

Uses & applications

Used in glass making, abrasive blasting, electronics (for its piezoelectric properties when pure), landscaping, and as a semi-precious stone for jewelry and tumbled stone collections.

Geological facts

Milky Quartz is the most common variety of crystalline quartz. While often overlooked by gem hunters in favor of clear rock crystal, it frequently contains gold in quartz vein deposits.

Field identification & locations

Identified by its white, cloudy appearance, hardness (scratches glass), and lack of cleavage. Look for it in quartz veins or as rounded pebbles in stream beds.