mineral

Amethyst

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

AI-generated identification · may be incorrect

Hardness 7 Mohs; translucent lavender-to-purple color, vitreous luster, trigonal crystal structure, and indistinct cleavage with conchoidal fracture. The visible piece appears rough and crystalline, though the image is too limited for certainty.

Identified September 13, 2026More mineral →

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Physical properties

Formation & geological history

Forms in silica-rich hydrothermal fluids, commonly lining cavities in volcanic basalt; crystals typically developed during cooling over geologic timescales, often in Mesozoic or younger volcanic rocks.

Uses & applications

Used as a gemstone, ornamental stone, carved objects, and mineral specimens; common pieces have modest commercial value.

Geological facts

Amethyst is the purple form of quartz and can fade with prolonged heating or strong sunlight. Its color intensity depends on iron content and irradiation.

Field identification & locations

Identify by its purple color, glassy luster, hardness, and lack of strong cleavage; it commonly occurs in geodes from Brazil, Uruguay, Mexico, Zambia, and Namibia. A definitive identification may require hardness and crystal-form testing.