Men's Solid Sterling Silver Rhodium Plated 12mm Puffed Mariner Chain Necklace, 30" For best results, we do strongly recommend using a tape measure to check neck size before placing your order. This necklace is made of solid rhodium plated sterling silver and stamped "925". This classic necklace looks great alone or with your favorite pendant. Necklace is 12mm thick, 30 inch long. (weight: 59.2 gram).