mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Identified March 22, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling and crystallization of silica-rich hydrothermal fluids in veins or as a late-stage mineral in igneous pegmatites. The milky appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used widely in manufacturing glass, ceramics, and optics. In industry, it is a source of silicon for electronics and solar panels. Lower quality specimens are used as decorative garden stones or construction aggregate.

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. It has piezoelectric properties, meaning it can generate an electric charge when mechanical stress is applied.

Field identification & locations

Identify in the field by its ability to scratch glass, its waxy white appearance, and lack of cleavage planes. It is ubiquitous globally and often found in riverbeds, mountain outcroppings, and gravel deposits. For collectors, look for pieces with distinct hexagonal crystal faces.