mineral

Clear quartz crystal

Quartz (silicon dioxide, SiO₂)

AI-generated identification · may be incorrect

Hardness 7 Mohs; colorless to smoky-clear, vitreous luster, transparent to translucent, and commonly hexagonal/trigonal crystal structure. The specimen appears rough or partly broken, with conchoidal fracture rather than obvious cleavage.

Identified September 6, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich hydrothermal fluids or cooling igneous melts precipitate quartz, often in veins and cavities. Quartz is common from Precambrian rocks through modern geological settings.

Uses & applications

Used for glass, electronics, abrasives, optics, and ceramics; clear crystals are collected and occasionally used in jewelry. This modest specimen has primarily educational or decorative value.

Geological facts

Quartz is one of Earth’s most abundant minerals and is piezoelectric, producing an electrical charge under pressure. Its apparent smoky tint may result from radiation-activated impurities, though lighting can also create that appearance.

Field identification & locations

Identify by its glassy luster, hardness sufficient to scratch ordinary glass, lack of cleavage, and six-sided crystal habit when preserved. Common localities include Brazil, Madagascar, the United States, Switzerland, and Arkansas.