mineral

Clear Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless/Transparent
Luster: Vitreous (glassy)

Identified July 12, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Quartz forms during the cooling of magma or by precipitation from hydrothermal veins. It is found in igneous, metamorphic, and sedimentary environments and can range from ancient Precambrian to relatively modern formations.

Uses & applications

Used widely in electronics (oscillators), glassmaking, abrasives, jewelry, and as healing crystals in alternative medicine.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'quarz', which originally meant 'hard'. Clear quartz is often called 'Rock Crystal'.

Field identification & locations

Identify in the field by its hardness (cannot be scratched by steel), glassy luster, and lack of cleavage. Found globally, especially in mountainous regions like the Alps, Himalayas, and Arkansas, USA.