mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2 + Fe)

Hardness: 7 (Mohs scale); Color: Pale lilac to deep royal purple, often with white bands (Chevron Amethyst); Luster: Vitreous/glassy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (Conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 (Mohs scale)
Luster: Vitreous/glassy

Identified February 14, 2026More mineral →

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Physical properties

Formation & geological history

Formed in primary cavities (geodes) of igneous rocks results from hydro-thermal processes or volcanic activity. The purple color is caused by irradiation of trivalent iron (Fe3+) in the quartz structure. While quartz is common across many geological ages, large deposits are often found in Cretaceous or Jurassic volcanic formations.

Uses & applications

Primarily used as a gemstone in jewelry, decorative carvings, and as biological/metaphysical healing crystals. Historically significant for jewelry and intaglios.

Geological facts

The name comes from the Ancient Greek word 'amethystos', meaning 'not intoxicated', as it was believed to protect its owner from drunkenness. It was once considered one of the Cardinal gems (equal to Diamond and Ruby) until large deposits were found in South America.

Field identification & locations

Identify in the field by its purple hue, lack of cleavage, and ability to scratch glass. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Tumbled specimens like this one are often found in rock shops and 'panning' kits.