mineral

Amethyst (Quartz variety)

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 (Mohs scale), Color: Purple to violet (zoning visible in this sample), Luster: Vitreous, Crystal Structure: Trigonal, Cleavage: None/Conchoidal fracture, Specific Gravity: 2.65

Identified April 16, 2026More mineral →

Identify your own rocks.

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

App Store Google Play

Physical properties

Hardness: 7 (Mohs scale), Color: Purple to violet (zoning visible in this sample), Luster: Vitreous, Crystal Structure: Trigonal, Cleavage: None/Conchoidal fracture, Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and geodes via precipitation from silica-rich fluids. The purple color comes from irradiation of iron impurities over millions of years.

Uses & applications

Primarily used as a gemstone in jewelry, decorative ornaments, and by mineral collectors for its aesthetic appeal.

Geological facts

Amethyst is the birthstone for February. Ancient Greeks believed it could prevent intoxication; the name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify in the field by its distinct purple color, hexagonal crystal shape (if unbroken), and ability to scratch glass. Found commonly in Brazil, Uruguay, and Africa.

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