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 19, 2026More mineral →

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 hydrothermal veins and cavities (geodes) of igneous rocks, particularly basalt, when silica-rich water precipitates in a void over time. The purple color is caused by gamma irradiation of trivalent iron impurities.

Uses & applications

Primarily used in jewelry (faceting and cabochons), decorative home decor (geodes), and as a popular collectable mineral specimen. Historically used as a symbol of nobility.

Geological facts

The name comes from the Greek word 'amethystos', meaning 'not intoxicated', as ancient Greeks believed it could prevent drunkenness. It is the birthstone for February.

Field identification & locations

Identify by its purple hue and hexagonal crystal habit (six-sided points). Commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors should look for deep, uniform color (deep Siberian) and high transparency.

Other mineral specimens

See all

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Schist

Metamorphic

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

metamorphic

Nephrite Jade

Nephrite

Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Green Apatite on Albite

Fluorapatite [Ca5(PO4)3F] on Albite [Na(AlSi3O8)]

mineral