mineral

Amethyst

SiO2 (Silicon Dioxide with Iron impurities and irradiation)

Hardness: 7 on Mohs scale; Color: Pale violet to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

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

Identified March 18, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Pale violet to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or as linings in volcanic geodes. The purple color results from the substitution of trivalent iron (Fe3+) for silicon and subsequent natural irradiation. It can be found in rocks from the Precambrian to Cenozoic eras.

Uses & applications

A semi-precious gemstone used extensively in jewelry (rings, necklaces), as decorative geodes/specimens for interior design, and historically as personal amulets.

Geological facts

Ancient Greeks believed amethyst could prevent intoxication. The name comes from 'amethystos,' meaning 'not drunken.' It is the birthstone for February.

Field identification & locations

Identify by its characteristic purple color, hexagonal prism shape, and lack of cleavage. It is commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors should look for color zoning and 'tiger stripe' inclusions.

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