Protective Finish for Copper
by Riki
(Israel)
How can one prevent copper from turning green and is there a coating that would protect the client's skin?
Thank you,
Riki
Stacy's Answer:
Thanks for your question, Riki. Copper will eventually turn green when exposed to air and moisture unless you protect it. There are a variety of materials used to protect copper...from waxes, which are temporary, to lacquers, which are more permanent. I generally prefer the lacquers.
Rio Grande makes a nice sealant called Midas® Finish Seal Lacquer, which is easy to apply and water soluble until it dries. However, I've found that the metal does continue to oxidize, albeit at a much slower rate, under the coating. It also wears off in areas that get a lot of friction.
My current sealant of choice is Permalac® EF because the fumes are not so noxious, it forms a nice hard shell and it does a better job of protecting the metal from further oxidation. The downside is that it's more difficult to use than Midas® and other sealers, though I've found it's worth the extra effort.