Regarding ring sizes, we have listed the inner diameter. (As we are unable to provide tools to measure ring sizes, there may be some slight discrepancies. We appreciate your understanding.) This is a retro ring with a natural stone. ◎ The metal is plated. Overall, there is discoloration, fading, scratches, and dullness. ◎ Inner diameter: Approximately 19mm (Approximately size 19) ◎ The stone is not glued to the setting, so it spins around on the frame. (It moves when touched, but it will not come off the frame.) ◎ The metal has scratches, discoloration, fading, and dullness.