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Look for keywords that indicate origin. Evaluate the trustworthiness of the seller. Find out if and how the emerald has been treated.

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“Created,” “lab created,” “laboratory grown” or “simulated” are keywords that indicate the emerald is synthetic, not natural. “Chatham” emeralds are also man-made. Be wary of the way a seller uses the word “genuine.” Created emeralds are indeed genuine synthetic emeralds, not genuine natural emeralds.  Jewelers may tout created emeralds as physically, visually and chemically the same as natural emeralds. However, they are nowhere near as valuable as natural emeralds. Other terms used for synthetic emeralds are Gilson, Inamori, and Seiko.  ”Imitation” emeralds are not the same as lab-created or  natural emeralds. They are various materials such as green glass or green cubic zirconia.  ”Composite” gemstone such as doublets or triplets are stones fused to other materials, such as an emerald top glued to a green glass bottom. Determining the value of colored gemstones takes years of experience. While you can do your own research, it’s best to utilize the guidance of a professional when considering such a large investment. Find a jeweler who has gemological credentials, is informed about emeralds, and has multiple natural emeralds with different styles that you can view simultaneously.  Research the place from which you are buying your emerald. There are many synthetic and imitation emeralds on the market, and it is imperative to be certain you are purchasing yours from a reputable dealer. Look for online reviews of the seller that come from a website other than the seller itself. Gemological credentials come from a educational organization like the Gemological Institute of America (GIA) or the American Gem Society (AGS). The jeweler will have initials after their name, such as RJ (Registered Jeweler) or CG (Certified Gemologist). You can look up the initials in a search engine to find out exactly how much education the seller has achieved in their field. Because they are prone to fractures, most emeralds are treated somehow. However, if the stone was significantly treated to improve its appearance and hide flaws, the emerald may appear higher quality than it actually is. If the stone was treated, find out whether the treatment is major or insignificant. Ask if the stone has been examined for fillers. Get a report from an independent laboratory that can confirm the emerald is natural and to what extent it’s been treated.  Don’t rely on a lab report that comes with the stone and is labeled as “independent.” Find your own, unbiased third party, such as a certified gemologist or appraisal organization. Stones may be sold without the seller disclosing the fact it was clarity enhanced, which is considered a deceptive practice.  Some polymer type resins will disintegrate and yellow with age. Avoid emeralds with certain oil treatments, as oils like cedar will cause yellow staining inside the stone after repeated oiling. Also remember all oil treatments will dry out and require re-oiling.