mineral

Polished purple quartz (likely amethyst)

Amethyst, a purple variety of quartz (SiO₂), possibly with iron-oxide staining or matrix

AI-generated identification · may be incorrect

Hardness 7 Mohs; translucent purple body with gray-brown/yellow surface material, vitreous luster, and conchoidal fracture. Quartz is trigonal and lacks cleavage; the small specimen appears naturally fractured and lightly polished or worn.

Identified August 23, 2026More mineral →

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Physical properties

Formation & geological history

Purple color forms when iron-bearing quartz is irradiated and later heated naturally, commonly in volcanic cavities and hydrothermal veins. Most amethyst formed during younger volcanic or hydrothermal events, often in basaltic geodes; exact age cannot be determined from the image.

Uses & applications

Used for cabochons, beads, carvings, mineral specimens, and ornamental objects; quartz is also important industrially. This tiny irregular piece has modest specimen value.

Geological facts

The purple color can fade with prolonged strong sunlight or heating. Its apparent yellow-brown coating may be limonite/goethite or attached host rock rather than part of the quartz.

Field identification & locations

Identify with glass-scratching ability, vitreous luster, and absence of cleavage; a crystal form, geode cavity, or iron staining would support amethyst identification. Common sources include Brazil, Uruguay, Zambia, and Mexico.