mineral

Amethyst

Amethyst (Silicon Dioxide - SiO2)

Hardness: 7 (Mohs scale); Color: Purple, violet; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Purple, violet
Luster: Vitreous (glassy)

Identified May 16, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Purple, violet; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Formation & geological history

Formed within volcanic rocks (basalts and rhyolites) from hydrothermal solutions as geothermal water cools and precipitates silica. The purple color comes from irradiation of iron impurities.

Uses & applications

Predominantly used as a gemstone for jewelry, in spiritual practices (metaphysical uses), and as decorative cabinet specimens for collectors.

Geological facts

Amethyst was considered a precious stone on par with Diamond and Ruby until large deposits were found in Brazil. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its characteristic purple color and hexagonal crystal points (if uncut). Found globally, notably in Brazil, Uruguay, and North America. It is the birthstone for February.