mineral

Amethyst

Amethyst (Silicon Dioxide - SiO2 with Iron impurities)

Hardness: 7 on Mohs scale; Color: Pale lilac to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Pale lilac to deep purple
Luster: Vitreous (glassy)

Identified April 7, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Pale lilac to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins and hollow geodes, typically when silica-rich solutions precipitate in cavities within igneous rocks. The purple color is caused by irradiation of trivalent iron (Fe3+) impurities within the quartz crystal lattice.

Uses & applications

Primary use is in jewelry as a semi-precious gemstone. It is also highly valued for crystal collecting, decorative home decor, and in alternative healing practices (metaphysical uses).

Geological facts

Amethyst was once considered one of the 'Cardinal Gems' alongside diamond, ruby, emerald, and sapphire, until large deposits were found in Brazil. The 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 characteristic purple hue and hexagonal prism crystal habit ending in a six-sided pyramid. It is commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors should look for deep, uniform color and high clarity without visible inclusions.

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