mineral

Cloudy Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White to pale grey-blue, translucent; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: White to pale grey-blue, translucent
Luster: Vitreous to waxy

Identified June 28, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to pale grey-blue, translucent; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the cooling of magma or hydrothermal activity in veins. Milky quartz gets its appearance from tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, jewelry (as cabochons), abrasives, and as a collectible metaphysical stone.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While often overlooked for clearer varieties, it can contain traces of gold in hydrothermal vein deposits.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and translucent 'milky' appearance. It is found globally in igneous and metamorphic environments.