mineral

Milky Quartz

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 June 9, 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

Formed through the crystallization of silica-rich hydrothermal veins or within igneous pegmatites. The milky appearance is caused by tiny fluid or gas inclusions trapped during crystal growth. Found in various geological ages worldwide.

Uses & applications

Used in glass making, abrasive materials, electronics (due to piezoelectric properties), and as decorative stones or carvings in jewelry and lapidary arts.

Geological facts

Milkiness is often due to microscopic inclusions of liquid or gas trapped within the crystal structure. It is the most common variety of crystalline quartz found on Earth's crust.

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and white opaque appearance. Commonly found in mountains, riverbeds, and as veins in metamorphic rocks. Collectors look for large, well-formed crystal clusters.