I am planning to compare trace element profiles of Bronze Age pottery with those of clay resources in Cyprus to determine interactions on the island during the Bronze Age.
Please contact Alexander Seyfert, the scientist with the hand held XRF, there is a lot of research and information done with this equipment in ares similar to your area of interest.
I would not recommend hand held XRF for ceramics unless you want nothing else than discriminating against various types of ceramics. If you need to have a full scale chemical analysis pls go for a benchtop XRF. This is the safe way to do precise and reliable analysis on ceramics.
Hand held XRF may probably do the job too, but the efforts needed for spot selection, preparation, setting up appropriate measuring conditions, interpreting the data and so on are huge and need a professional.
So in a short answer: If you are XRF erperienced, hand held is an option. I you are unexperienced in XRF, keep your hand OFF hand held machines!