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 May 2, 2026More mineral →

Explore Amethyst in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

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

Formed in geodes or cavities within igneous rocks through hydrothermal processes. The purple color is caused by irradiation of trivalent iron impurities (Fe3+) in the quartz structure. Most commercial specimens are from the Mesozoic era.

Uses & applications

Primarily used in jewelry, as decorative collector specimens, and in alternative healing practices (metaphysical uses).

Geological facts

Amethyst is the birthstone for February. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect its owner from drunkenness.

Field identification & locations

Identified by its purple color and hexagonal prism shape. Commonly found in Brazil, Uruguay, Zambia, and Ontario. Collectors look for deep 'Siberian' purple hues and clear transparency.