The lacy red agate stone can not be fired in a kiln, so it has to be set another way. Bezel setting is the traditional method, although not the only method.
In the Arrowmont earring class, we had to bezel set a stone and set a stone using an investment stand in. This pair of earrings demonstrates the traditional bezel set.
In metal clay it can be done in two different ways. One is to make the bezel and push it into the damp clay. This method can cause a distortion to the clay and possible cracking. During my Level 2 class, we used this method and five out of the seven pieces cracked. But all was not lost as necessity is the mother of invention (as they say). Those five pieces now have beautifully decorated backs which cover up the cracks.
The other method, which I did here, is to make the background piece and fire it. Make the bezel piece and either solder or fire it, then join the two pieces together with lavender paste and fire again. This method allows the background piece to stay flat (or domed as in this case) without distortion.