mineral

Clear Quartz (Rock Crystal)

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 March 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: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed from silica-rich hydrothermal solutions or magmatic cooling in pegmatites. It can be found in rocks of all geological ages, often in veins or cavities.

Uses & applications

Used in electronics for its piezoelectric properties, glass manufacturing, abrasives, jewelry (as a gemstone), and metaphysical collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Rock crystal has been used since ancient times for carving 'crystal balls' and decorative ornaments.

Field identification & locations

Identify in the field by its ability to scratch glass, its colorless transparency, and its curved, shell-like (conchoidal) fracture pattern. It is commonly found globally, particularly in mountain ranges and riverbeds.