mineral

Amethyst (rough crystal cluster)

Quartz, SiO₂; purple color from trace iron and natural irradiation

AI-generated identification · may be incorrect

Mohs hardness 7; purple to violet, vitreous luster, trigonal crystal structure, no cleavage, and conchoidal fracture. The specimen is a rough cluster of translucent-to-opaque quartz crystals.

Identified October 7, 2026More mineral →

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Physical properties

Mohs hardness 7; purple to violet, vitreous luster, trigonal crystal structure, no cleavage, and conchoidal fracture. The specimen is a rough cluster of translucent-to-opaque quartz crystals.

Formation & geological history

Amethyst crystallizes from silica-rich fluids in cavities, commonly in volcanic rocks; its age varies with the host deposit, often millions to hundreds of millions of years.

Uses & applications

Used for jewelry, carvings, decorative specimens, and collecting; most amethyst is valued as an ornamental gemstone rather than an industrial material.

Geological facts

The label identifies it as a rough amethyst cluster, apparently graded and priced at about $175; color intensity and clarity strongly affect value.

Field identification & locations

Recognize it by purple quartz crystals with glassy luster and hardness near 7; major sources include Brazil, Uruguay, Zambia, and other volcanic regions. Avoid scratching crystals when testing, since hardness tests can damage the specimen.