Stripping Gold and Nickel from Copper

A. Larry, I've found the best way strip nickel from copper copper is a proprietary, cyanide-based immersion strip. There are several available and your choice will depend on what type of nickel you are trying to strip (electroless, sulfamate, etc.). Check with nickel plating chemical suppliers. The gold can easily be stripped from the nickel with a similar cyanide based stripper.

A. Larry- I must respectfully disagree with Keith. Cyanide will attack (dissolve) copper much faster than it will nickel. Any cyanide stripper which will go through the nickel will then proceed to attack the underlying copper, leaving pits, streaks, etc. The printed circuit industry faces this problem often, and there are proprietary non-cyanide strippers available for this application. Check with chemical suppliers who service this industry.