Ametrine mined in Bolivia is a natural form of quartz that shows the colors of amethyst and citrine in the same gem. This gem is genarally considered to be of natural untreated color. Ametrine is usually cut in emerald cut gems to make them bi-color. You will see this orientation and cutting styles that mix the colors on our website. Both are unique and beautiful at an extremely reasonable price. Beware synthetic material is manufactured in Russia.