mineral

Amethyst quartz cluster

Quartz, SiO₂; purple coloration from trace iron and irradiation

AI-generated identification · may be incorrect

Mohs hardness 7; purple to gray color, vitreous luster, hexagonal crystal structure, and no true cleavage but conchoidal fracture. The specimen appears to be a naturally terminated or partly worn crystal cluster, possibly with druzy quartz and iron staining.

Identified September 7, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich hydrothermal fluids or volcanic cavities deposit quartz; the amethyst color develops through iron impurities and natural radiation. Most commercial material formed in Cenozoic to Precambrian volcanic or geode environments.

Uses & applications

Used as a jewelry gemstone, ornamental mineral, meditation object, and collector specimen; high-quality transparent crystals are faceted, while clusters are commonly displayed.

Geological facts

Amethyst is the purple variety of quartz and is February’s birthstone. Heating can turn it yellow-orange, producing citrine-like material.

Field identification & locations

Identify by purple color, glassy luster, hardness sufficient to scratch glass, and six-sided quartz crystals; common sources include Brazil, Uruguay, Zambia, Namibia, and Mexico. Avoid prolonged strong sunlight, which may fade the color.