mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2)

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

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

Identified March 25, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins and basaltic geodes. The purple hue is caused by irradiation, iron impurities, and the presence of trace elements. It is found in deposits ranging from millions of years old to relatively recent geological formations.

Uses & applications

Predominantly used as a gemstone in jewelry, for decorative carvings, and as aggregate specimens for mineral mineral collectors and metaphysical practitioners.

Geological facts

Ancient Greeks believed amethyst could prevent intoxication. It has been used for royal jewelry for centuries and was once considered as valuable as diamonds or rubies until large deposits were found in Brazil.

Field identification & locations

Identify by its distinctive purple color and inability to be scratched by a steel knife. It is commonly found in Brazil, Uruguay, and Namibia. In the field, look for hexagonal prismatic crystals inside vugs or cavities in volcanic rock.