Hi, I just purchased a Tiffany sapphire cobblestone ring on Poshmark and was relying on their authentication process to make sure it’s a real Tiffany piece. But I’ve since read that their process is fallible so am second guessing my purchase (especially since I bought it for a little more than 1/3 of the price). I’ve also seen two different types of Tiffany stamps on this ring and not sure if they ever change stamps depending on when it was made or consistently use one. Since Tiffany’s doesn’t authenticate their jewelry, what is the next best option? Getting a professional appraisal? Any suggestions would be greatly appreciated. Thanks.