mineral

Amethyst

Amethyst (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 14, 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 igneous and sedimentary environments, often occurring as linings within geodes. The purple color is caused by irradiation and iron impurities in the quartz structure. These can date back millions of years depending on the host rock formation.

Uses & applications

Commonly used in jewelry, decorative items, and as a popular specimen for mineral collectors. Historically used to ward off intoxication.

Geological facts

Amethyst is the birthstone for February. Its name comes from the Greek word 'amethystos', meaning 'not intoxicated', as ancient Greeks believed the stone protected its wearer from drunkenness.

Field identification & locations

Identify by its distinctive purple color and quartz-like vitreous luster. In the field, look for volcanic basalt cavities or hydrothermal veins. It can be distinguished from purple fluorite by its much higher hardness (it will scratch glass).

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