mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

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

Identified June 8, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from silicon-rich hydrothermal fluids or within igneous pegmatites. The white 'milky' appearance is caused by microscopic inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), and as decorative gravel or landscaping stone. Low-grade specimens are common in beginner rock collections.

Geological facts

Milky quartz is one of the most common mineral varieties on Earth. It is often found in veins that cross-cut other rock types and can sometimes be a host rock for gold.

Field identification & locations

Identified in the field by its hardness (will scratch glass), lack of cleavage, and white opaque color. Found globally in almost every geological environment.