mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

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 July 4, 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 (basalt) or hydrothermal veins. The purple color is caused by trace amounts of iron and natural irradiation over millions of years.

Uses & applications

Extensively used in jewelry, as decorative display pieces, for crystal healing collections, and as February's birthstone.

Geological facts

Amethyst was considered a precious stone equal to diamond until large deposits were found in Brazil. The name comes from the Greek word 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its characteristic purple color and hexagonal prismatic crystal shape appearing in clusters. Common locations include Brazil, Uruguay, Africa, and Canada.