Next up on my list of gemstones is, Ametrine. Ametrine is a member of the Quartz family of gemstones, and is Purple Quartz or Amethyst, and Yellow Quartz or Citrine, that form together creating Ametrine. Ametrine is a natural forming gemstone, not man made, and is almost exclusively found in Bolivia. There are treatments available to enhance color and quality. a 50/50 split stone is the most prized of all Ametrine. Below is a video from the GIA explaining Ametrine much better than I can. I do not have any Ametrine in my current gemstone collection.