This is an authentic TIFFANY Platinum Diamond .51ct Solitaire Engagement Ring size 51 or 5.75. The ring is crafted of platinum and features a sparkling round brilliant cut diamond weighing approximately .51 carats, with E color and SI1 clarity. Follow this item for alerts. Tiffany is a registered trademark of Tiffany. FASHIONPHILE is not affiliated with Tiffany.