For a project I’m working on I wanted to test to oxidize copper to get it to look old and used so I read up on the internet and got some ideas. So I got hold of the chemicals I wanted to test with.

  • Ammonia
  • Table salt (fine, flake and coarse)
  • Hydrochloric Acid
  • Citric Acid

Some texts indicated that you could apply Ammonia get the oxidizing to start of and add acid and salt to speed up the process and improve the patterns.

The first three tests I performed was to soak a bit of paper towel in ammonia and press it against the piece of copper with salt of three different coarseness between. The second test was to apply water, acid and salt onto a piece of copper and have Ammonia fumes react.

The result

The top three is Ammonia in a paper towel pressed against the copper with salt, fine, flakes and coarse. The bottom two is coarse salt and ammonia fumes, with hydrochloric acid and citric acid on the copper pieces.