mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

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

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

Identified July 8, 2026More mineral →

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Physical properties

Hardness: 7 on the Mohs scale; Color: Purple, violet, or lavender; 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 fills cavities in volcanic rocks (like basalt). The purple color comes from irradiation of iron impurities over millions of years.

Uses & applications

Extensively used in jewelry (faceting, cabochons, beads), decorative carvings, and as a popular metaphysical or collectible specimen.

Geological facts

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

Field identification & locations

Identified by its distinctive purple hue and hardness (it will scratch glass). Often found in Brazil, Uruguay, and Zambia. Look for hexagonal crystal terminations in its raw form.