mineral

Rock crystal (clear quartz)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Colorless to cloudy, glassy luster, with irregular fracture and no obvious cleavage; Mohs hardness 7, trigonal crystal structure, specific gravity about 2.65. The specimen appears massive and fractured rather than a well-formed crystal.

Identified October 13, 2026More mineral →

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Physical properties

Formation & geological history

Quartz forms when silica-rich fluids crystallize in veins and cavities, or during igneous and metamorphic processes. It is among Earth’s most abundant minerals and occurs in rocks of many geological ages.

Uses & applications

Used for jewelry, ornaments, glassmaking, and as an industrial source of silica; clear, attractive pieces are collected or cut into gems.

Geological facts

Quartz is piezoelectric, producing an electrical charge under pressure, which makes it useful in clocks and electronic components.

Field identification & locations

Identify by its glassy appearance, hardness sufficient to scratch ordinary glass, and lack of cleavage; common worldwide in veins, pegmatites, and sedimentary deposits. The photo’s translucent, fractured material is consistent with quartz, though visual identification is not definitive.