mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7.0 on Mohs scale. Color: Opaque white to translucent. Luster: Vitreous to greasy. Crystal Structure: Hexagonal (Trigonal). Cleavage: None (Conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7
Color: Opaque white to translucent
Luster: Vitreous to greasy

Identified March 16, 2026More mineral →

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Physical properties

Hardness: 7.0 on Mohs scale. Color: Opaque white to translucent. Luster: Vitreous to greasy. Crystal Structure: Hexagonal (Trigonal). Cleavage: None (Conchoidal fracture). Specific Gravity: 2.65.

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal fluids in veins or as a primary constituent in igneous rocks like granite. Its white color is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the production of glass, ceramics, and sandpaper. In electronics, it is used for its piezoelectric properties. It is also used as decorative garden stone, in jewelry (as cabochons), and for healing stone collections.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of crystalline quartz found in nature. In ancient times, some believed quartz was permanently frozen ice.

Field identification & locations

Identify in the field by its ability to scratch glass, its milky white color, and the lack of cleavage (it breaks in irregular, curvy pieces). Commonly found in mountain ranges, stream beds, and gravel pits globally.