I bought this ring from a jade jewelry shop in Thailand. This thumb ring is size 11 and is a natural (untreated) jade ring carved with a dragon on it. See photos and videos for colors and details. This ring doesn't come with any certificate. Inner diameter 20.87mm Wideness 16.37mm Thickness 4mm The inner part of the ring isn't polished. Only the outer side is polished. Please feel free to ask any questions before making a purchase. Thanks for looking.