mineral

Clear Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

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

Identified July 20, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Quartz forms in a wide variety of environments, most commonly by crystallizing from molten magma (igneous), precipitating from hydrothermal veins, or through the metamorphism of silica-rich rocks. It can be found in rocks from nearly every geological era.

Uses & applications

Used extensively in glass making, electronics (piezoelectric applications), abrasives, jewelry (as a gemstone), and as high-quality decorative specimens for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'Quarz', which likely stems from a Slavic root meaning 'hard'. It is the primary mineral in common sand.

Field identification & locations

Identified by its crystal habit (six-sided prisms with pyramids), its ability to scratch glass, and its lack of cleavage (it breaks with curved, shell-like surfaces). Found worldwide, with significant deposits in Brazil and Arkansas, USA.