mineral

Amethyst

Quartz (Silicon Dioxide with iron impurities), SiO2

AI-generated identification · may be incorrect

Hardness: 7 Mohs; Color: Purple/Violet; Luster: Vitreous; Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

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

Identified July 19, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: Purple/Violet; Luster: Vitreous; Crystal Structure: Hexagonal (trigonal); 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, impurities of iron, and the presence of trace elements. Found in rocks ranging from Precambrian to Cenozoic.

Uses & applications

Primarily used in jewelry, as a healing crystal in alternative medicine, and as a popular collectible specimen.

Geological facts

Amethyst was once considered one of the five cardinal gemstones until large deposits were found in Brazil. Its name comes from the Greek word 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identified by its purple color and hexagonal crystal habit. Common in Brazil, Uruguay, and Zambia. Collectors should look for deep uniform color and lack of inclusions.