mineral

Amethyst (Tumbled)

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 on Mohs scale; Color: Purple/Violet; Luster: Vitreous; Crystal Structure: Hexagonal (Trigonal); Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Purple/Violet
Luster: Vitreous

Identified May 5, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple/Violet; Luster: Vitreous; Crystal Structure: Hexagonal (Trigonal); Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins or geodes when silica-rich water precipitates in gas cavities of volcanic rocks. The purple color is caused by natural irradiation of trace amounts of iron.

Uses & applications

Widely used in jewelry (rings, necklaces), as decorative omaments, and highly valued by mineral collectors and practitioners of crystal healing.

Geological facts

Until the 18th century, amethyst was included in the cardinal gemstones alongside diamond, ruby, emerald, and sapphire. Its name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its characteristic purple hue and lack of cleavage. It is most commonly found in Brazil and Uruguay. Collectors should look for deep, uniform color and clarity.

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