mineral

Amethyst cluster

Amethyst, purple quartz (SiO₂)

AI-generated identification · may be incorrect

Purple, glassy luster, with visible quartz crystal points; Mohs hardness 7, trigonal crystal system, and no true cleavage. The specimen appears to be a small, rough crystal cluster.

Identified October 1, 2026More mineral →

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Physical properties

Purple, glassy luster, with visible quartz crystal points; Mohs hardness 7, trigonal crystal system, and no true cleavage. The specimen appears to be a small, rough crystal cluster.

Formation & geological history

Amethyst forms as quartz crystals lining cavities in volcanic rocks, with trace iron and natural radiation producing its purple color. Such deposits formed over a range of geological ages; the image does not reveal a specific locality or age.

Uses & applications

Used in jewelry, ornamental objects, and mineral collections; lower-grade material is sometimes carved or used as décor.

Geological facts

Amethyst is the purple variety of quartz; heat can alter its color, sometimes producing citrine-like hues.

Field identification & locations

Identify by its purple color, glassy quartz crystals, and hardness; common sources include Brazil, Uruguay, Zambia, and parts of the United States. A small common cluster like this typically sells for about $5–$30, depending on color, crystal quality, and origin.