mineral

Amethyst

Silicon Dioxide with Iron impurities (SiO2)

Hardness: 7 on Mohs scale; Color: Pale lavender to deep royal purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Pale lavender to deep royal purple
Luster: Vitreous (glassy)

Identified March 25, 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: Pale lavender to deep royal purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and hollow cavities (geodes) within igneous rocks. The purple color results from irradiation of iron impurities over millions of years. Common in volcanic basalt and metamorphic deposits.

Uses & applications

Primary use is in jewelry as a semi-precious gemstone. Also highly popular for metaphysical collecting, architectural decor (large geodes), and as a February birthstone.

Geological facts

Ancient Greeks believed amethyst could prevent intoxication; the name comes from the Greek 'amethystos', meaning 'not drunken'. It was once considered one of the 'cardinal gems' alongside diamond and ruby until large deposits were found in Brazil.

Field identification & locations

Identify by its purple hue and ability to scratch glass. Found heavily in Brazil, Uruguay, Zambia, and South Korea. Collectors look for deep saturation and lack of visible inclusions.

Other mineral specimens

See all

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

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

Epidote

Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)

mineral