mineral

Quartz (Milky or Cloudy Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White to off-white/translucent; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: White to off-white/translucent
Luster: Vitreous to greasy

Identified April 6, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to off-white/translucent; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich magma or precipitation from hydrothermal veins. It can be found in a wide variety of igneous, metamorphic, and sedimentary environments across all geological ages.

Uses & applications

Used in glassmaking, abrasives, electronics (due to piezoelectric properties), construction as aggregate, and in jewelry as semi-precious gemstones. Large specimens are popular with collectors.

Geological facts

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

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage, and its waxy or vitreous luster. It is found globally, often in riverbeds, mountains, and desert sands.

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