mineral

Milky Quartz

Crystalline Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Cloudy white to tan (due to iron oxidation)
Luster: Vitreous to greasy

Identified March 6, 2026More mineral →

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Physical properties

Formation & geological history

Forms through the cooling of silica-rich hydrothermal veins or within igneous pegmatites. This specimen likely originated from a vein that was subsequently weathered and tumbled by alluvial processes.

Uses & applications

Used industrially as a source of silica for glassmaking, abrasives, and electronics. Common varieties are used in landscaping, low-cost jewelry, and as decorative stone.

Geological facts

The milky appearance is caused by microscopic inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz found on the Earth's surface.

Field identification & locations

Identified in the field by its hardness (scratches glass), lack of cleavage, and waxy luster on fractured surfaces. Found globally in almost any geological environment, particularly in mountain runoff and arid plains.