mineral

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Hardness: 7 on Mohs scale; Color: White to opaque/cloudy; Luster: Vitreous (glassy) to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: White to opaque/cloudy
Luster: Vitreous (glassy) to greasy

Identified April 13, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to opaque/cloudy; Luster: Vitreous (glassy) to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Formation & geological history

Formed through the cooling of silica-rich hydrothermal veins or the crystallization of magma. The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, electronics (due to piezoelectric properties), and as a gemstone or decorative garden stone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is often the most common variety found in nature and can sometimes contain veins of gold.

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage, and its characteristic white 'milky' opacity. It is found globally in almost all geological environments.