that question calls for an experiment! my stuff is all packed up for moving right now so i can't try it out but i will say that the copper coating is almost thin enough to scratch off with a fingernail.

try this:
the reaction occur every time clean steel comes into contact with the liquid so leave the object in the pickle and dip several more pieces of steel. bits of wire will work just fine as the reaction depends on creating a charge and not how much material is used. let me know what happens!

Hi Jason, this copper coat thing is interesting but tricky I guess. Can you copper plate, or copper coat steel as it is done electrolitically with Zn and Ni? I`ve disolved Cu sulphate and stick a steel bar in the solution and it gets a thin Cu coat deposited on its surface. The coating is better when the steel is wet in acetic acid (vinegar). The problem is that the very thin Cu coat is thin and not bound really to the steel surface molecules, because it`s easily scratched off...I`m going to look into the process and some metal plating/coating forum to find out more. Should something interesting come up, I will let you know. Nelson.

it really is the low budget method

generally when people create this reaction it isn't on purpose

i'm always looking for interesting way to put color on steel.

speaking of which, keep an eye out!