Because the stated value of a diamond can vary widely depending on the integrity of the retailer and the practices of a laboratory, it is very important to make sure your dealer stands behind his merchandise. The best way to do this is with a warranty guaranteeing the value or return purchase. This way, you can have confidence that you are not paying an inflated price. Furthermore, it is important to make sure your dealer is well-established and can be contacted anytime. Check their credentials as gemologists and their business registration to make sure they are not an "overnight" shop. It won't help you to have any certificates or warranties if the shop is empty the day after you buy the diamond. This also goes for visiting salespersons- it would be best to make at least one visit to their business before actually buying anything from them.
