finishing a copper bezel on a silver backing sheet.

[Trish]

I have made a silver ring with a copper bezel setting on a silver base, it looks good but I want to set a moonstone and don't want the copper to turn green inside after I have set the stone. can anyone suggest a coating or lacquer i could use on the copper to prevent it tarnishing without it forming a thick skin? I thought about using nail varnish or even thinned down nail varnish ,has anyone any better ideas ?

[mizgeorge]

I think I'd go with a microcrystalline wax (Renaissance).

If it's good enough for the British Museum.....

I think I'd avoid anything that could crack or peel.

However, if the bezel is really well rubbed over, it shouldn't let enough air in for the copper to oxidise badly. At the worst, I'd have thought it would only darken rather than turn green.