|Variations in color|
I put the piece of metal on a tripod and heated it from underneath moving the torch around so as not to overheat the metal. When a color I liked magically appeared on the surface I removed the heat. If you hold the torch without moving it you get something that looks like this. The back of the metal is black because it got really hot, but I think this will make a nice earring. I just let the sheet of copper cool naturally so I could watch the colors emerge and decide it I wanted to hit it again with heat.
Getting the patina to stay can be an issue because the lacquers will muddy the colors and dull the finish. Here is a forum where people suggest different products but I am just going to let nature take its course and see what happens. I'll post some jewelry I make out of this sheet and let you know about finishes as I experiment further. I have read that you can also patina in an oven but that wouldn't be nearly as much fun.
If you got questions, leave me a comment and I'll do my best.