mineral

Amethyst (Tumbled)

Quartz (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 (Mohs), Color: pale purple to deep violet, Luster: Vitreous (glassy) when polished, Crystal structure: Trigonal (often seen in raw form, obscured here by tumbling), Cleavage: None (conchoidal fracture)

Identified September 3, 2026More mineral →

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Physical properties

Formation & geological history

Forms in geodes or vugs in volcanic rocks, as well as in hydrothermal veins. The purple color is due to irradiation of iron impurities.

Uses & applications

Commonly used in jewelry, decorative arts, crystal healing practices, and as collector specimens.

Geological facts

Amethyst is the birthstone for February. It was historically considered as valuable as ruby or emerald until large deposits were found in Brazil.

Field identification & locations

Identified by its distinctive purple color and quartz hardness (can scratch glass). Commonly found in Brazil, Uruguay, and Zambia.

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Placer deposit concentrate containing minerals such as ilmenite, rutile, zircon, and magnetite

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Epidote

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