mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Identified June 19, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque; 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 solutions in veins or during the cooling of igneous rocks like granite. The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, ceramics, abrasives, and as a source of silicon for electronics. In jewelry, it is often used for beads, cabochons, and decorative carvings.

Geological facts

Quartz is the second most abundant mineral in the Earth's continental crust. Milky quartz is the most common variety of quartz found in nature, often occurring in massive veins that can be several meters thick.

Field identification & locations

Identify by its ability to scratch glass, lack of cleavage, and characteristic waxy-to-glassy luster. It is ubiquitous globally, commonly found in gravel pits, riverbeds, and mountainous regions.