These processes cause chemical reactions that are hazardous to one's health and the environment! Don't attempt these experiments without first learning how to do them safely.
I generally process karat gold, but I was sent a somewhat processed chunk of metal that was believed to contain a fare amount of gold. But is it enough gold to make it worth the effort? Some refining is done just for the joy of it. A hobby, like most, that isn't cost effective, but still brings joy. And heck, you do end up with gold in the end! For me, I have to process material that contains enough gold to cover my time and materials. This is a test to see if electronic waste is worth my effort.