Hi Debbie, thats really a complex piece of work you are planning.
Although I´ve not worked with carved stones (yet) some thoughts come to my mind....
First thing is, I dont think a carved back of your pendant will cause discomfort (assuming you will carve it in shallow relief).
The way how you may set the amethysts depends -I my opinion- mostly from the thickness of your chrysoprase. If thick enough I think carving a recess for the amethysts is the most elegant way (depending of course also on the quality of your stones... I would be a pity if you set a perfecty translucent stones that way).
To fasten the goldsettings a UV curing glass glue would be cool (I dont like the bilging of epoxy) or - more traditionaly- kundan technique. Maybe the stone carvers around here have some more and better ideas.
