mineral
Amethyst (Tumbled)
Silicon Dioxide (SiO2 with iron impurities)
Hardness: 7 (Mohs scale), Color: Purple to violet, Luster: Vitreous (glassy), Crystal Structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65
Identified More mineral →
Explore Amethyst (Tumbled) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 7 (Mohs scale), Color: Purple to violet, Luster: Vitreous (glassy), Crystal Structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65
Formation & geological history
Formed in hydrothermal veins and cavities (geodes) of igneous rocks, particularly basalt. The purple color is caused by gamma irradiation of iron impurities.
Uses & applications
Commonly used in jewelry (faceting and cabochons), crystal healing, interior decoration, and as a popular entry-level mineral specimen for collectors.
Geological facts
Amethyst is the birthstone for February. The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect the wearer from drunkenness.
Field identification & locations
Identify in the field by its distinct purple color, hexagonal crystal habits (when raw), and ability to scratch a glass plate. Commonly found in Brazil, Uruguay, and Africa.
More like this
Other mineral specimens
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Schist
Schist
Metamorphic
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Gypsum (variety Selenite or Alabaster)
Calcium sulfate dihydrate (CaSO4·2H2O)
Mineral
Nephrite Jade
Nephrite
Mineral/Rock
Banded Gneiss (River Rock/Pebble)
Gneiss (specifically a banded variety often found as a river rock)
Metamorphic Rock