We have been making pots for over 40 years with emblems on them - Celtic knots and crosses for shops in Scotland and Wales, or more site specific ones such as a little Imp for Lincoln Cathedral and the Durham Knocker for Durham Cathedral.
The emblems are made by pushing clay into an engraved plaster mould which Gerry has always made himself. At the moment we are working on a little acorn mould for the Little Yorkshire Candle Company. They sell reed diffusers and wanted some little pots for the oil containers.
A couple of photos of pots with emblems on:-