There's a product called "ProtectaClear" that you can coat copper, brass, etc. It will keep it from tarnishing and is safe to handle. It can be used on jewelry. I haven't tried it yet but I would like to get some to treat my Copper. It's about 20 bucks for a kit. Look up "Everbrite" and you should be able to find it. If I do get some, I report my findings here on the ECF. Thanks....