mineral

Quartz (specifically Clear Quartz or Rock Crystal)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale), Color: Colorless/Transparent, Luster: Vitreous (glass-like), Crystal Structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified June 17, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Colorless/Transparent, Luster: Vitreous (glass-like), Crystal Structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed from the cooling of silica-rich magma or precipitation from hydrothermal solutions. It is found in igneous, metamorphic, and sedimentary environments and can range from millions to billions of years old.

Uses & applications

Used in electronics (oscillators), optics (glass making), construction (sand/aggregate), jewelry (gemstones), and as decorative collector specimens.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the Greek word 'krustallos' meaning ice, as ancient Greeks believed it was ice that had frozen so hard it would never melt.

Field identification & locations

Identify by its ability to scratch glass, its lack of cleavage (it breaks in curved, shell-like patterns called conchoidal fractures), and its vitreous luster. It is common in riverbeds, mountains, and pegmatite veins worldwide.