mineral

Amethyst (as seen in jewelry)

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None; Specific Gravity: 2.65

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

Identified June 7, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None; Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) of igneous rocks when silica-rich solutions crystallize. The purple color is caused by irradiation of trivalent iron (Fe3+).

Uses & applications

Primarily used as a gemstone in jewelry (rings, pendants, earrings), decorative items, and as collectible mineral specimens.

Geological facts

Amethyst was considered a precious stone equal to diamond until large deposits were found in Brazil in the 19th century. The name comes from the Ancient Greek word 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its distinctive purple color and hexagonal prism habits in raw form. In the field, it is often found lining the inside of volcanic geodes in regions like Brazil, Uruguay, and Zambia.

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