mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 on Mohs scale
Color: White to translucent
Luster: Vitreous (glassy) to greasy

Identified April 11, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. They can form across all geological ages.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), and as a gemstone or decorative garden stone. Massive varieties are used in construction aggregates.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz. It can sometimes contain inclusions of gold in hydrothermal veins.

Field identification & locations

Identify by its ability to scratch glass, its lack of cleavage, and its waxy/glassy luster. It is ubiquitous globally and often found in mountain ranges, beaches, and desert environments.