There are a number of threads in our archives regarding enameling, Eutectic solder and IT solder. Click on the magnifying glass located on the upper right to begin a search.
Another option when using fine silver is to fuse the bezel on the backplate, no solder needed.
In addition, Barbara Lewis's version of torch enameling includes information about allowing the enamel to attach and hold together pieces of metal, instead of using solder. This idea vaguely reminds me of cloisinne, but I doubt a bezel would remain securely embedded in the enamel when you push on the bezel wire to set the stone.
Setting the stone would be my last step after the enameling is finished, and I would never heat the stone.
I wonder if drilling a hole in a fine silver backplate would contribute to undermining the strength of the entire plate? I'm thinking specifically about stretching enough to lose the stone. I would consider setting the entire enameled piece into a bezel.
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