mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque; 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 opaque
Luster: Vitreous to greasy

Identified June 13, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from hydrothermal veins and cooling magma (pegmatites). It results from gas bubbles or inclusions of liquid trapped during the crystal's growth, which scatter light and create the milky appearance.

Uses & applications

Used in glassmaking, ceramics, as an abrasive, and extensively as a gemstone or decorative garden stone. High-purity quartz is used in electronics for its piezoelectric properties.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically gets its appearance from microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Identify by its hardness (will scratch glass), lack of cleavage, and white waxy look. It is commonly found in gravel pits, mountain ranges, and as river pebbles globally.