mineral

Amethyst crystal

Quartz, SiO₂; purple variety colored mainly by iron impurities and irradiation

AI-generated identification · may be incorrect

Mohs hardness 7; pale violet to purple, vitreous luster, transparent to translucent, hexagonal crystal structure, and no true cleavage (conchoidal fracture). The specimen appears to be a small rough crystal fragment, possibly with clear quartz zones.

Identified August 23, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich hydrothermal fluids fill cavities in volcanic rocks, especially basaltic geodes; crystallization commonly occurred in the Cenozoic or older volcanic episodes. Exact age and locality cannot be determined from the image.

Uses & applications

Used as a gemstone, ornamental material, and mineral-collection specimen; also sold for metaphysical purposes. It is not generally used as a structural or industrial stone.

Geological facts

Amethyst’s purple color can fade with prolonged heating or strong sunlight; heating may produce yellow citrine-like material. Natural color zoning and crystal faces help distinguish it from dyed glass.

Field identification & locations

Common sources include Brazil, Uruguay, Zambia, Bolivia, and Mexico; identify by hardness, glassy luster, conchoidal fracture, and lack of bubbles or flow texture. A close view and locality information would improve identification.