mineral

Amethyst cluster

Amethyst, purple variety of quartz (SiO₂)

AI-generated identification · may be incorrect

Vitreous luster; purple crystals with hexagonal structure, typically Mohs hardness 7 and no cleavage. The specimen appears to be a rough crystal cluster, possibly with a cut or broken base.

Identified October 1, 2026More mineral →

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Physical properties

Vitreous luster; purple crystals with hexagonal structure, typically Mohs hardness 7 and no cleavage. The specimen appears to be a rough crystal cluster, possibly with a cut or broken base.

Formation & geological history

Amethyst forms as quartz crystals in gas cavities of volcanic rocks, often over millions of years; its purple color is caused by iron impurities and natural irradiation. The exact geological age and locality cannot be determined from the image.

Uses & applications

Used in jewelry, ornaments, and mineral collections; lower-grade material is also used for decorative objects.

Geological facts

Amethyst is quartz colored by trace iron and radiation; heating can turn some amethyst yellow or orange, resembling citrine.

Field identification & locations

Identify by its purple, glassy quartz crystals and hardness sufficient to scratch glass; common sources include Brazil, Uruguay, Zambia, and other volcanic regions. Avoid assuming locality from appearance alone.