mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified June 27, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the crystallization of silica-rich hydrothermal fluids in veins or as a major constituent of igneous rocks like granite. The milky appearance is caused by tiny liquid or gas inclusions trapped during crystal growth.

Uses & applications

Used in the production of glass, ceramics, and electronics (due to piezoelectric properties). Often used as a landscaping decorative stone or for lapidary work like cabochons.

Geological facts

Quartz is the most abundant mineral in the Earth's crust. Milky quartz is a common variety and can often be found as 'river rocks' due to its high resistance to weathering.

Field identification & locations

Identify by its ability to scratch glass, its waxy to vitreous luster, and lack of cleavage planes. Commonly found in riverbeds, mountain ranges, and sedimentary gravel deposits globally.