mineral

Ametrine

Silicon Dioxide (SiO2) with impurities of iron

Hardness: 7 on Mohs scale; Color: Bicolor purple (amethyst) and yellow/orange (citrine); Luster: Vitreous (glassy); Crystal structure: Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Bicolor purple (amethyst) and yellow/orange (citrine)
Luster: Vitreous (glassy)

Identified May 24, 2026More mineral →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Formed in hydrothermal veins or pegmatites when temperature gradients cause iron impurities to reach different oxidation states within the same quartz crystal. Nearly all natural commercial ametrine comes from the Anahi mine in Bolivia.

Uses & applications

Primarily used in jewelry as a gemstone and for crystal healing/metaphysical collection. Smaller specimens are popular for lapidary art.

Geological facts

Ametrine is one of the rarest naturally occurring gemstone varieties in the world because it requires a very specific temperature gradient to exist during its formation. It was first introduced to Europe in the 17th century by a Spanish conquistador.

Field identification & locations

Identify by looking for the distinct, sharp transition between purple and yellow sections within a single vitreous crystal. Naturally found almost exclusively in the Santa Cruz department of Bolivia.

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

Biotite Schist

Biotite-rich Schist [K(Mg,Fe)3AlSi3O10(F,OH)2]

metamorphic