Pickling Copper and Brass

[Tiggy_dorset]

Regarding the citric acid and brass/copper bit, check out the Yank gun forums. Seems to be quite widely used for cleaning up spent cartridges, along with tumbling.

Been testing it on some brass here recently, and bar the fact that you can get the patchy copper/brass effect which needs polishing out, it does a decent enough job of cleaning the stuff. If you dunk owt in there which has oxidised notably though, it will be pitted once the citric has removed the corrosion.

Regarding steel, you basically end up with a mildly acidic iron rich solution. Some plants will love that.

You are indeed correct I just spoke to the gardener of the household who confirmed what you say. Unfortunately we have no plantoids which would benefit from it. So down the drain it goes.