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 February 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 the cooling of silica-rich magma or through hydrothermal activity in veins. It can be found in virtually all geological environments and across all geological ages, often as the final mineral to crystallize in pegmatites.

Uses & applications

Used in electronics (oscillators and clocks) due to piezoelectric properties, glassmaking, abrasive blasting, jewelry (faceted stones and beads), and as metaphysical healing crystals.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Historically, it was used to make ancient 'crystal balls' and was believed by some cultures to be permanently frozen ice.

Field identification & locations

Identify by its ability to scratch glass, its six-sided prismatic shape with terminal pyramids, and lack of cleavage planes. Common locations include Brazil, Arkansas (USA), and Madagascar. Collectors look for clarity and well-defined crystal faces.

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