mineral

Amethyst (Variety of Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Purple, violet; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

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

Identified May 30, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) within igneous and metamorphic rocks. The purple color is caused by irradiation of iron impurities within the quartz structure.

Uses & applications

Widely used as a gemstone in jewelry (rings, necklaces, earrings), as decorative specimens for collectors, and in alternative healing practices. High-quality pieces are faceted into gems.

Geological facts

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

Field identification & locations

Identified by its purple color, 6-sided prismatic crystals when intact, and inability to be scratched by steel. Commonly found in Brazil, Uruguay, and South Korea. Collectors should look for deep, uniform color (known as Deep Siberian) for maximum value.