mineral

Clear Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Transparent to colorless. Luster: Vitreous (glassy). Crystal Structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific Gravity: ~2.65.

Hardness: 7 on Mohs scale
Color: Transparent to colorless
Luster: Vitreous (glassy)

Identified July 26, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: Transparent to colorless. Luster: Vitreous (glassy). Crystal Structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific Gravity: ~2.65.

Formation & geological history

Forms in a wide variety of geological environments, including igneous pegmatites, hydrothermal veins, and metamorphic rocks, through the cooling of silica-rich fluids or crystallization from magmatic sources.

Uses & applications

Widely used in jewelry, decorative carvings, optical equipment, glass manufacturing, and electronics (due to its piezoelectric properties). Popular as a metaphysical and gemstone specimen.

Geological facts

Clear quartz, historically known as rock crystal, was believed by ancient Greeks to be ice that was permanently frozen so deeply it could never melt.

Field identification & locations

Identified by its transparency, vitreous luster, hardness of 7 (scratches glass, cannot be scratched by a steel knife), and lack of true cleavage. Commonly found worldwide, with major sources in Brazil, Arkansas (USA), and Madagascar.