mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

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

Identified February 14, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal solutions or cooling magma in veins and pegmatites. It is the most common variety of crystalline quartz, owing its cloudiness to microscopic inclusions of fluid or gas trapped during growth.

Uses & applications

Used in the manufacturing of glass and ceramics, as an abrasive in sandpaper, in the production of silicon for electronics, and as decorative stone for landscaping and jewelry.

Geological facts

Milky quartz is the most common mineral on the Earth's continental crust. Its distinct white color is caused by millions of tiny bubbles of gas or liquid that were trapped when the crystal formed millions of years ago.

Field identification & locations

Identify by its 'milky' white appearance and the fact it can easily scratch glass but cannot be scratched by a steel knife. It is ubiquitous globally, often found in mountain ranges, creek beds, and as large veins in igneous rock outcrops.