Ametrine, aka trystine or by its trade name as bolivianite, is a naturally occurring variety of quartz. It is a mixture of amethyst and citrine with zones of purple and yellow or orange. Amethyst

Ametrine, aka trystine or by its trade name as bolivianite, is a naturally occurring variety of quartz. It is a mixture of amethyst and citrine with zones of purple and yellow or orange.