Mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 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 on Mohs scale
Color: Opaque white to translucent
Luster: Vitreous to greasy

Identified March 8, 2026More mineral →

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Physical properties

Hardness: 7 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 from the cooling of silica-rich hydrothermal fluids or magma. Its white color is caused by tiny fluid inclusions (bubbles of gas or liquid) trapped during crystal growth. It can be found in igneous, metamorphic, and sedimentary environments worldwide.

Uses & applications

Used in the gemstone industry for carvings and beads, in the glass-making industry as a source of silica, and as an abrasive. In landscaping, it is used for decorative gravel.

Geological facts

Milky quartz is the most common variety of crystalline quartz. Historically, it has been used for stone tools when flint was unavailable. Large, pure masses can contain enough fluid inclusions to appear perfectly snowy white.

Field identification & locations

Identify in the field by its hardness (will scratch glass but cannot be scratched by a steel knife) and lack of cleavage (it breaks in irregular, curved shards). Found commonly in veins or as river pebbles. Collectors should look for clear crystal points or iron-stained 'Golden Healer' variations.