mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Colorless and transparent to translucent. Luster: Vitreous (glass-like). Crystal structure: Hexagonal/Trigonal. Cleavage: Indistinct. Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Colorless and transparent to translucent
Luster: Vitreous (glass-like)

Identified July 24, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: Colorless and transparent to translucent. Luster: Vitreous (glass-like). Crystal structure: Hexagonal/Trigonal. Cleavage: Indistinct. Specific Gravity: 2.65.

Formation & geological history

Forms through crystallization from magmatic pegmatites, hydrothermal veins, and metamorphic rocks across various geological ages.

Uses & applications

Used in jewelry, decorative carvings, optical instruments, electronics (piezoelectric oscillators), and highly sought after by mineral collectors.

Geological facts

Clear Quartz is one of the most abundant minerals on Earth's continental crust. Historically, ancient Greeks believed clear quartz was ice that had frozen so deeply it could never melt.

Field identification & locations

Identified by its hexagonal crystal habits, hardness 7 (scratches glass, cannot be scratched by a steel knife), and clear glassy appearance. Common in Brazil, Madagascar, the US (Arkansas, New York), and the Alps.