mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale), Color: Colorless/Transparent, Luster: Vitreous/Glassy, Crystal Structure: Trigonal, Cleavage: None/Conchoidal fracture, Specific Gravity: 2.65

Identified July 11, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Colorless/Transparent, Luster: Vitreous/Glassy, Crystal Structure: Trigonal, Cleavage: None/Conchoidal fracture, Specific Gravity: 2.65

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments through the cooling of silica-rich magma or from hydrothermal veins. It is found in geological formations ranging from billions of years old to relatively recent ones.

Uses & applications

Used in electronics (as piezoelectric crystal), high-end glass manufacturing, jewelry, watch movements, and as a popular metaphysical or decorative specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Rock crystal was once believed to be ice that had frozen so hard it could never melt.

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and transparent clarity. It is commonly found in riverbeds, mountains, and mining sites worldwide, notably in Brazil and Arkansas, USA.