mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Identified May 24, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the crystallization of silica-rich hydrothermal fluids in veins or pegmatites. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, as a flux in metallurgy, and in electronics for its piezoelectric properties. Common in landscaping and as a decorative mineral for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is specifically white because of 'fluid inclusions'—microscopic bubbles of water or gas trapped for millions of years.

Field identification & locations

Identify by its white color, lack of cleavage, and ability to scratch glass easily. It is found globally in almost all geological environments, particularly in quartz veins.