mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

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

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

Identified June 22, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins and basaltic geodes. The purple color is caused by gamma irradiation of trivalent iron impurities and structural defects in the quartz lattice. Common in volcanic regions.

Uses & applications

Widely used for jewelry (birthstone for February), decorative ornaments, metaphysical purposes, and as a popular collector specimen.

Geological facts

Amethyst was once considered one of the five cardinal gemstones alongside diamonds and rubies until large deposits were found in Brazil. The name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identified by its purple color and hardness (it can scratch glass). Found globally, with major deposits in Brazil, Uruguay, and Zambia. Collectors look for deep saturation and clarity.

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Mineral/Rock

Banded Gneiss (River Rock/Pebble)

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Metamorphic Rock

Green Apatite on Albite

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mineral