mineral

Amethyst (in jewelry)

Silicon Dioxide (SiO2) with iron impurities

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

Hardness: 7 on Mohs scale
Color: Purple, violet
Luster: Vitreous

Identified May 4, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed within hydrothermal veins or volcanic geode cavities. The purple color is caused by irradiation of iron impurities within the quartz structure. Most specimens range from late Paleozoic to Cenozoic eras.

Uses & applications

Primary use is in jewelry as gemstones (rings, brooches, necklaces). Also used for ornamental carvings and popular among mineral collectors.

Geological facts

Amethyst was once considered one of the 'Cardinal Gems' along with diamond and emerald until large deposits were found in Brazil. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its distinct purple hue and quartz-like transparency. Commonly found in Brazil, Uruguay, and Africa. As jewelry, look for hallmarks on the metal setting for authenticity.

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