This is not quite IH, but close enough to merit a mention.
As I am recovering old electrical wires whilst gradually doing up my (1950s) house, I wondered how is the copper recovered from these wires (and those inside WEEE separated electrical equipment).
I searched on Youtube (the home of just about anything!) and, among others, found this video, where an individual recovers the copper from old wire as a one man project, making ingots out of same.
I’m not sure of the economics of it, but judging by his collection (at the end of the video), it is an interesting way to pass the time and retain some metals at the end of it.