mineral

Amethyst (Cabochon)

Silicon Dioxide (SiO2) with iron impurities

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

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

Identified April 21, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins or geodes when silica-rich water cools. The purple color is caused by trace amounts of iron and high-energy radiation (natural or artificial) after the crystal has formed.

Uses & applications

Predominantly used as a gemstone in jewelry, decorative ornaments, and by mineral collectors for its aesthetic and spiritual perceived value.

Geological facts

Amethyst is the birthstone for February. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect the wearer from drunkenness.

Field identification & locations

Identify by its distinct purple hue, inability to be scratched by a steel knife, and lacks cleavage (it breaks with a conchoidal fracture). In the field, it is often found lining the interior of basaltic or volcanic cavities (geodes).

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