Mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque white; Luster: Vitreous (glassy) to greasy; Crystal structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

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

Identified March 26, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque white; Luster: Vitreous (glassy) to greasy; Crystal structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. The white color is caused by tiny liquid or gas inclusions trapped during crystal growth. They can be found in rocks of almost any geological age.

Uses & applications

Used in the manufacturing of glass and ceramics, as an abrasive in sandpaper, in silicon microchips, and as a decorative stone in landscaping or jewelry (cabochons).

Geological facts

Milky Quartz is the most common variety of crystalline quartz. It is often found in large veins that can be hundreds of feet long. Historically, quartz has been used for tool making (stone age) and as a symbolic healing stone.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and translucent 'white' appearance. Common worldwide, especially in mountain ranges and stream beds. Collectors should look for well-formed crystal points.