mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

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

Identified July 17, 2026More mineral →

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Physical properties

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

Formation & geological history

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

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), landscaping, and as a collector's stone or decorative tumble.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While often overlooked for clearer varieties, large veins of milky quartz are often indicators of gold deposits in hydrothermal systems.

Field identification & locations

Identify by its ability to scratch glass, lack of cleavage, and white 'milky' opacity. It is found globally in almost every geological environment, particularly in mountainous regions and riverbeds.