mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: White to cloudy translucent, Luster: Vitreous to greasy, Crystal Structure: Hexagonal (trigonal), Cleavage: Indistinct/Conchoidal fracture, Specific Gravity: 2.65

Identified May 3, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: White to cloudy translucent, Luster: Vitreous to greasy, Crystal Structure: Hexagonal (trigonal), Cleavage: Indistinct/Conchoidal fracture, Specific Gravity: 2.65

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal fluids in veins or as a primary mineral in igneous and metamorphic rocks across all geological eras.

Uses & applications

Used in glass making, abrasive manufacturing, electronics (due to piezoelectric properties), and as decorative gravel or low-cost gemstone/jewelry elements.

Geological facts

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

Field identification & locations

Identify by its hardness (scratches glass), waxy/glassy luster, and lack of cleavage. Commonly found in riverbeds, mountain veins, and as cobbles in sedimentary deposits.