mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 on Mohs scale
Color: Cloudy white to semi-opaque
Luster: Vitreous to greasy

Identified March 22, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to semi-opaque; 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 magma or through hydrothermal activity in veins. The white color is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth. Can be found in geological environments ranging from Precambrian to Cenozoic.

Uses & applications

Used in the production of glass, ceramics, and abrasives. High-purity quartz is used in electronics for oscillators. In jewelry, it is often used for beads or cabochons. Widely used as landscaping stone and decorative gravel.

Geological facts

Milky Quartz is the most common variety of crystalline quartz. It is often found in the same veins as gold, making it a key indicator for prospectors. Some specimens contain 'ghost' crystals or phantoms inside.

Field identification & locations

Identify in the field by its waxy-to-glassy white appearance and the fact that it cannot be scratched by a steel knife. Common in mountainous regions, riverbeds, and as garden mulch. It often displays a characteristic 'blocky' or conchoidal fracture pattern.