gemstone

Small purple quartz crystal, likely amethyst

Amethyst: violet variety of quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Typically Mohs hardness 7, vitreous luster, hexagonal crystal structure, and no cleavage; purple color comes mainly from iron impurities and irradiation. The specimen appears naturally crystal-faced and translucent, though its tiny size limits certainty from the image.

Identified August 10, 2026More gemstone →

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Physical properties

Formation & geological history

Forms when silica-rich hydrothermal fluids or gas cavities in volcanic rocks deposit quartz; amethyst commonly grows in basalt vesicles and geodes, generally from Phanerozoic volcanic settings. Common sources include Brazil, Uruguay, Zambia, and Mexico.

Uses & applications

Used as a jewelry gemstone, ornamental material, and mineral-collection specimen; small crystals have modest commercial value.

Geological facts

Amethyst is the traditional February birthstone and was historically regarded as protection against intoxication. Heating can produce yellow citrine-like material.

Field identification & locations

Look for purple coloration, glassy luster, hardness sufficient to scratch ordinary glass, and six-sided crystal faces or druzy texture. Likely locations include volcanic geodes and hydrothermal veins; value is usually about $1–$10 for a tiny rough crystal, or $10–$50 if unusually clear and well formed.