mineral

Amethyst (rough crystal cluster)

Quartz, SiO₂; purple coloration commonly caused by trace iron and natural irradiation

AI-generated identification · may be incorrect

Mohs hardness 7; purple, translucent-to-transparent crystal tips over a pale, opaque matrix. Vitreous luster, trigonal crystal system, and no true cleavage; uneven to conchoidal fracture. The matrix may be another mineral or host rock and cannot be identified confidently from the image.

Identified September 25, 2026More mineral →

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Physical properties

Formation & geological history

Amethyst forms when silica-rich fluids deposit quartz in cavities and fractures, with trace iron and irradiation producing purple color. Such deposits occur in rocks of varied ages, including volcanic geodes and hydrothermal veins.

Uses & applications

Used in jewelry, carvings, and mineral collections; lower-grade material may be used for ornaments or decorative stone.

Geological facts

Amethyst is the purple variety of quartz, and its color can fade with prolonged exposure to strong sunlight or heat.

Field identification & locations

Look for purple quartz crystals with pointed hexagonal terminations and a glassy luster; common sources include Brazil, Uruguay, Zambia, and other quartz-bearing regions. The specimen appears to be a small rough cluster, but its locality and matrix are uncertain from the photo.