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 June 4, 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 from the cooling of silica-rich hydrothermal fluids or magma in veins and pegmatites. The milky appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), various industrial fillers, and as a decorative stone in landscaping or lapidary work.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically is common in gold-bearing veins and is often used by prospectors as an indicator mineral for precious metals.

Field identification & locations

Identify by its white color, inability to be scratched by a steel knife, and lack of cleavage. It is found globally in almost all geological environments but most prominently in hydrothermal veins.