mineral

Amethyst

SiO2 (Silicon Dioxide with iron impurities)

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

Hardness: 7 on Mohs scale
Color: Purple/Violet
Luster: Vitreous/Glassy

Identified March 3, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins or as linings within volcanic rock cavities (geodes). The purple color results from irradiation of trivalent iron impurities within the quartz crystal lattice.

Uses & applications

Primary use is in jewelry and lapidary arts as a semi-precious gemstone. Also highly valued as a collector specimen and popular in the metaphysical community for decorative purposes.

Geological facts

Amethyst was considered a 'Cardinal Gem' until the 18th century, ranked alongside diamonds and rubies in value until major deposits were discovered in Brazil. Its name comes from the Greek word 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify in the field by its distinctive purple hue, hexagonal prism crystal habits, and ability to scratch glass. Commonly found in Brazil, Uruguay, Madagascar, and the Lake Superior region of North America.

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