I've been busying in the pottery lately, and this is what I've come up with.
They consist of a rolled out piece of clay which is then cut and left until "leather hard". I then set to work with a sharp knife and clay needle to engrave into the surface of the tile to make little reservoirs for the glass to sit. The tiles are bisque fired and then the glass is put in and they get a glaze firing so the bits of glass melt into a lovely gloop. They're now ready to hang on the wall with one small nail.
I shall be listing the "Home Sweet Home" one in my shop this week, but the rest I'm reluctant to sell as they're my first go. I'll be whipping up some more soon though! There's already one in progress that features fir trees and a small owl. Twit twoo!