TOUS Yunque signet ring with 18 kt gold plating over silver with central openwork motif and 17 mm mother-of-pearl inner disc. Openwork charm size: 18.64 mm. Charm thickness: 3 mm. Ring thickness: 3 mm. It is made of sterling silver with 18 to 23kt gold plating and has a thickness of 3 microns. This quality guarantees a greater durability of the jewel.