This is a ring base with a bezel setting, similar to a claw setting. I purchased this, but it doesn't fit the stones I have, so I'm selling it. Stamped SV925, plated. I'm not sure what kind of plating it is. Below is the seller's description: ------------ Stone size: Up to 5.7mm thick ※ Approximately 7.6 x 9.2 ~ 8.0 x 10.0mm compatible ※ Adhesive required for stones thicker than 5.7mm Ring size: Free size (adjustable from size 7 to 23)