In Washington State you used to have to either have a business license or wait two weeks to get a check in the mail for scrapped nonferrous metals. Not any more, now you get paid the same day. There are many grades of copper. If you strip like-new welding lead and bring in gleaming 100% copper coils, they call that no. 1 copper and it carries the most money. If you turn in scrapped out copper pipe with lots of solder joints and the occasional valve which has a cast zinc handle, that will be like no. 3 copper and it doesn't bring as much. Insulated wire brings less money, but it all is recyclable. By the way, the method used to remove insulation from a lot of fine insulated wire is interesting. A machine chops up the wire into particles like fine sand, and they are dropped through a cross-blast of air. The insulation being lighter than the metal, it goes sideways while the metal drops more or less straight down.
metalmagpie