fusing objects in glass
It is my understanding that you can drill a small hole for the stone to sit in and full fuse. You can use either a cz or a swarovski crystal(more colors, sizes and less expensive). I have fused both in metal clay at temperatures much higher than fusing temps and for longer with 100% success. Anyway, it can be done, but do experiment a little before hand, so you know how deep to drill the hole.