mineral

Amethyst

Silicon Dioxide (SiO2) with trace Iron (Fe3+)

Hardness: 7 mohs. Color: Purple to violet. Luster: Vitreous. Crystal structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Hardness: 7 mohs
Color: Purple to violet
Luster: Vitreous

Identified May 2, 2026More mineral →

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Physical properties

Hardness: 7 mohs. Color: Purple to violet. Luster: Vitreous. Crystal structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins and basaltic geodes. The purple color is caused by irradiation of iron impurities within the quartz crystal structure.

Uses & applications

Primarily used in jewelry, decorative arts, and as a popular collector's specimen. It is the birthstone for February.

Geological facts

The name comes from the Greek 'amethystos', meaning 'not intoxicated', as ancients believed it prevented drunkenness. Leonardo da Vinci once wrote that amethyst could dissipate evil thoughts.

Field identification & locations

Identify by its distinct purple color and hardness (it can scratch glass). Commonly found in Brazil, Uruguay, and Zambia. In the field, look for hexagonal crystal prisms in geode pockets.

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