I don't see any markings, but I was told by the shop that it's a silver ring. Size is unknown, but I think it would fit if it's around 6.5. How about layering it with other rings? Silver tends to tarnish, but the blackening can be removed by polishing or using a special cleaner, and it will become shiny again. I will ship it via regular mail. I am not responsible for any postal accidents. If you would like tracking, you can upgrade to Mercari delivery for an additional 50 yen, so please comment before purchasing. #Ring #SilverRing