Copper plating, experiment #1

I know this isn't exactly about crystals, but science is fun anyway, right? ;)

In an earlier experiment, read here, I made a copper acetate solution from copper wire, now I want to try copper plating using that solution. This will just be a simple experiment without too much explanation, I'll save that for the next time.

So first things first, we need something to copper plate. I will use a 5 kr coin that's made of a copper/nickel alloy with a nickel core. You need to clean the coin thoroughly to remove all dirt and grease from the surface. I soaked the coin in some acidic acid (vinegar) and cleaned it of with rubbing alcohol.

Connect some copper, I'll use copper wire, to the positive terminal of a 9V battery and the coin to the negative. Place the two in the copper acetate solution and let it react.

After about 15 min I took the coin out of the solution and I was a bit disappointed in how it looked, burned and stained. But with some rubbing with metal polish, the nice copper finish started to come out.  

This is a comparison on how it looks next to an untreated coin. Copper plating on the left and a normal coin on the right.

It was a fun experiment and I will revisit it to make improvements.