More on impure copper wire

You cannot ball the ends of wire pieces using a torch with the impure copper wire if you're into that in your jewelry making.

Impure Copper Wire

I have just discovered that impure copper wire is being sold in some craft stores.  I had to stop and do some clean up at the bench and while picking up some copper wire cut offs that missed getting a little container I have for that purpose, that some of the wire stuck to pair of tweezers that happened to be magnetized.  I checked some of the spools of copper wire with a magnet and the wire stuck to the magnet, indicating it was not pure copper as sold.  Maybe this won't make a difference to you in your work, but it should.