mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO₂)

Hardness: 7 on Mohs scale; Color: White to translucent; 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 translucent
Luster: Vitreous (glassy) to greasy

Identified March 22, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to translucent; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed through the cooling and crystallization of silica-rich magma or through hydrothermal activity in veins. It is found in all geological ages and across every type of rock environment (igneous, metamorphic, and sedimentary).

Uses & applications

Used in the manufacture of glass, ceramics, and abrasives. High-purity quartz is essential in electronics (oscillators) and solar panels. Varieties are used as gemstones and in decorative carvings.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. 'Milky quartz' gets its 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 (it breaks in irregular, shell-like curves), and its white or clear color. Found globally in mountains, riverbeds, and as beach sand.