mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

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

Identified May 27, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins and pegmatites through the crystallization of silica-rich fluids. Milky quartz specifically gets its opaque color from microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), gemstones, garden landscaping, and as an abrasive in sandblasting.

Geological facts

Milky quartz is the most common variety of crystalline quartz. It is often found as the 'mother' rock for gold in hydrothermal vein deposits. Some specimens can be billions of years old.

Field identification & locations

Identified in the field by its hardness (scratches glass), lack of cleavage, and white 'cloudy' appearance. It is ubiquitous in riverbeds and mountainous terrain worldwide.