mineral

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Clear to translucent; Luster: Vitreous (glassy); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Clear to translucent
Luster: Vitreous (glassy)

Identified April 1, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Clear to translucent; Luster: Vitreous (glassy); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It is found in all types of geological environments and can be found in rocks from almost every geological age.

Uses & applications

Used in electronics (oscillators), glass manufacturing, abrasives, jewelry (gemstones), and as a popular collector's mineral.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is piezoelectric, meaning it generates an electric charge when mechanical pressure is applied.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), its glassy luster, and the presence of curved, shell-like (conchoidal) fractures rather than flat cleavage planes. Found globally in mountains and riverbeds.