mineral

Rock crystal quartz fragments

Quartz (silicon dioxide, SiO₂)

AI-generated identification · may be incorrect

Hardness 7 Mohs; colorless to milky-clear, vitreous luster, translucent, and commonly displaying conchoidal fracture rather than cleavage. The irregular broken surfaces suggest rough quartz rather than a complete crystal.

Identified August 28, 2026More mineral →

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Physical properties

Formation & geological history

Quartz crystallizes from silica-rich hydrothermal fluids, pegmatites, and igneous or metamorphic environments; individual pieces may range from recent to billions of years old. The image alone cannot determine its exact geological age or locality.

Uses & applications

Used in glass and ceramics, abrasives, foundry sand, electronics, and ornamental specimens; clear crystals are also used in jewelry and metaphysical collecting.

Geological facts

Quartz is one of Earth’s most abundant minerals and has piezoelectric properties, producing an electrical charge under pressure. It can resemble clear calcite or man-made glass, but quartz is significantly harder.

Field identification & locations

Common worldwide, including Brazil, Madagascar, Arkansas, and the Alps. Field tests include scratching glass with an edge and checking for curved fracture; a steel knife generally will not scratch it.