mineral

Raw quartz crystal (likely citrine or iron-stained quartz)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Hardness 7 Mohs; translucent pale yellow to colorless, with vitreous luster and irregular/conchoidal fracture. Quartz is trigonal and lacks cleavage; the apparent yellow color may result from iron staining or heating.

Identified August 15, 2026More mineral →

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Physical properties

Formation & geological history

Forms in hydrothermal veins, pegmatites, and cavities in igneous rocks; individual crystals may form over millions of years. The image alone cannot establish geological age or distinguish natural citrine from heat-treated amethyst.

Uses & applications

Used for glass, electronics, abrasives, and construction aggregate; transparent attractive pieces are sold as gemstones or mineral specimens. Small rough specimens commonly have modest value.

Geological facts

Quartz is one of Earth’s most abundant minerals and is piezoelectric. Natural citrine is relatively uncommon compared with commercially heat-treated amethyst.

Field identification & locations

Look for glassy luster, hardness sufficient to scratch steel or ordinary glass, and no cleavage; quartz crystals commonly show six-sided prisms and pyramidal tips. Common localities include Brazil, Madagascar, Uruguay, and the United States.