Milky Quartz

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 from the cooling of magma or hydrothermal veins where hot silica-rich solutions cool and crystallize. Found in igneous, metamorphic, and sedimentary environments across all geological ages.

Uses & Applications

Used in glassmaking, abrasives, gemstones (cabochons), clocks and electronics (piezoelectric properties), and as decorative landscaping stones.

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 on Earth.

Field Identification & Locations

Identify by its hardness (scratches glass), white color, and lack of cleavage. Often found in vein deposits or as pebbles in rivers and beaches; extremely resistant to chemical weathering.

Identified on: 4/29/2026

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