We use the two well-known & most trusted laboratory for appraisals - Universal Gemological Laboratories, UGL & International Gemological Institute, IGI. They are known for their integrity and fair value of diamonds and diamond jewelry. Keep in mind that if you planned on insuring your diamond, you will need an appraisal. It helps later on if, G-d forbid, you should have a loss, you will not have to argue with your insurance adjuster about who appraised your diamond, since you will have an independent apprasial availible, not an appraisal from the store you bought it from.