To determine if ametrine is real, you can follow these steps: 1. Look for color zoning: It typically exhibits both purple amethyst and yellow citrine color zones. If the gemstone shows a clear separation of colors, it's likely to be genuine. 2. Check for transparency: Real ametrine should have good transparency, allowing light to pass through without any cloudiness or impurities. 3. Observe the color transition: Genuine ametrine crystals should have a smooth and natural transition between the purple and yellow colors, without any abrupt changes. 4. Assess the cut: Gemstones are usually cut to maximize the visibility of both colors. A well-cut ametrine will enhance its beauty and display the color zoning clearly. 5. Consider the source: It is mined in Bolivia, so if the gemstone is claimed to be from another location, it may be a red flag. Please note that these methods can provide a general indication, but for a definitive confirmation, it's always recommended to consult with a professional gemologist or jeweler.