mineral

Amethyst (Tumbled)

Crystalline Quartz (SiO2 with iron impurities)

Hardness: 7 (Mohs scale); Color: Purple to violet due to irradiation and iron impurities; Luster: Vitreous (glassy); Crystal structure: Trigonal (Hexagonal system); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Purple to violet due to irradiation and iron impurities
Luster: Vitreous (glassy)

Identified April 9, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins or as linings in volcanic geodes (vugs). The purple color results from the presence of iron (Fe3+) in the crystal lattice that has been exposed to ionizing radiation during or after formation.

Uses & applications

Extensively used in jewelry (rings, necklaces, earrings), ornamental carvings, and as a popular collectible item for crystal healing or aesthetic home decor.

Geological facts

Amethyst was considered a precious stone in ancient times, equal in value to diamond, until large deposits were found in Brazil in the 18th century. Its name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identified by its distinctive purple hue and hexagonal crystal faces (when not tumbled). It is commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors look for deep 'Siberian' purple saturation with red or blue flashes.

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