Since now I am curious and I had to work today I tried laser welding
copper. I had to turn up all the settings higher than even silver
and still could barely get a weld and they were very brittle even
with the argon. I was using some 18 gauge copper sheet and some
small electrical wire for filler.
So next I tried with the same materials welding with a Little Torch
on oxy- propane. I managed to get some very messy weldlike fusing on
the molten surface It was weird and very hard to control, but the
result was not brittle. Without a lot of practice you couldn't do
much but really rough innaccurate fabrication and nothing very
For small jewelry items I bet copper could be lasered or brazed with
silver or gold wire- didn't think of it until now-might work
better(or not). But you'd have to check that the melting
temperatures of the various alloys was high enough for enameling.