Yes, You can use the enamel itself to hold a setting for a stone.
It’s touchy. If the metal gauge is too heavy, it will pop off; if the
bezel isn’t clean or the enamel isn’t thick enough it will pop or
crack off. If the enamel comes up the sides of the bezel too far, you
won’t have enough metal to hold the stone, if you put too much
pressure on the bezel when setting the stone, you can pop it out of
the enamel.
Don’t ask me for specifics, as I work by experimentation/intuition.
Have fun.
Marianne