mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2)

Hardness: 7 (Mohs scale); Color: Purple/Violet; Luster: Vitreous/Glassy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (Conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Purple/Violet
Luster: Vitreous/Glassy

Identified July 4, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Purple/Violet; Luster: Vitreous/Glassy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (Conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Forms through hydrothermal processes in cavities within volcanic or sedimentary rocks. The purple color is caused by irradiation of iron impurities within the quartz crystal structure. Common in ages from Precambrian to modern.

Uses & applications

Extensively used in jewelry (rings, necklaces, carvings), as a collector's specimen, and in holistic practices. It was historically used as a gemstone for royalty.

Geological facts

The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', due to a belief that the stone protected its owner from drunkenness. It is the birthstone for February.

Field identification & locations

Identified by its distinctive purple hue and crystal habit. Commonly found in Brazil, Uruguay, and Zambia. Collectors look for deep violet saturation and high clarity.