mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Identified July 12, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments. Milky quartz specifically gets its cloudy appearance from microscopic inclusions of gas or liquid trapped during crystal growth in hydrothermal veins.

Uses & applications

Used as a source of silica for glassmaking, abrasive in sandblasting, decorative landscaping, and occasionally in jewelry as cabochons or tumbled stones.

Geological facts

Quartz is one of the most abundant minerals in the Earth's continental crust. The 'milky' look is caused by fluid inclusions (bubbles) that scatters light within the crystal.

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and white color. Found globally in riverbeds, mountains, and beaches. Collectors value large, well-formed crystals over water-worn pebbles.