mineral

Amethyst

Amethyst (Varietal of Quartz), SiO2 (Silicon Dioxide)

Hardness: 7.0 on Mohs scale; Color: Purple, violet, to deep lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7
Color: Purple, violet, to deep lavender
Luster: Vitreous (glassy)

Identified March 14, 2026More mineral →

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Physical properties

Hardness: 7.0 on Mohs scale; Color: Purple, violet, to deep lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and hollow cavities (geodes) of igneous rocks. The purple color comes from irradiation of iron impurities within the silicon dioxide crystal structure during formation.

Uses & applications

Predominantly used as a gemstone in jewelry (rings, necklaces, earrings). It is also highly popular as a decorative mineral specimen and in artisanal carvings.

Geological facts

In ancient times, Amethyst was believed to prevent intoxication; the word comes from the Greek 'amethystos', meaning 'not drunk'. It is the birthstone for February and was once considered as valuable as diamonds until large deposits were found in Brazil.

Field identification & locations

Identify by its distinctive purple color and hexagonal growth patterns (six-sided prisms). It can be found in massive geodes in Brazil and Uruguay, and in veins in North Carolina, Arizona, and Zambia. In tumble-polished form like the specimen shown, identify by its clarity and hardness.

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