Why are Green Amethysts Green?
Green amethyst is produced when heat is applied to a certain type of amethyst. Most amethyst turns yellow, orange or brown when heated, but amethyst containing iron compounds with specific properties (Fe2+ iron compounds) will turn green instead. Some natural sources green quartz has been found, however the green amethyst sold as gemstones is heat-treated. The two are the same – it is speculated that heat produced naturally by geological events during formation of the mineral caused the production of the naturally green deposits.
