mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to tan/brown due to weathering; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white to tan/brown due to weathering
Luster: Vitreous to greasy

Identified June 10, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich hydrothermal veins or within igneous pegmatites. The 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. They can be found in rocks from practically any geological age.

Uses & applications

Used as a gemstone (cabochons), in glass making, as an abrasive, and in the manufacturing of oscillators for watches and electronics. Also used as decorative landscaping stone.

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.

Field identification & locations

Identify by its hardness (cannot be scratched by a steel knife) and its lack of cleavage. It is commonly found in riverbeds as rounded 'river rocks' or as veins in mountain outcrops worldwide.