Unlike the ceramics from an excavation, sherds collected during field survey are not stratified. This makes it very difficult to date sherds and to reconstruct ceramic assemblages. Dating evidence is by association only, if a sherd is found with a datable sherd of bucchero it can be assumed to be from the same period as the bucchero. However, if a sherd is found with bucchero, fine creamware and black gloss ware it is not possible to date the sherd more closely than after the earliest date for bucchero and before the latest date for the black gloss; perhaps a period of five hundred years. Occasionally a site is found where the period of occupation, or more usually deposition in the case of tombs, is short and a group of pottery can be closely dated. But these sites are rare and since they are usually tombs, this situation does not often aid the dating of ceramics from settlement sites because there are generalised qualitative differences between the ceramics deposited in tombs and those discarded at settlements; a comparison of the ceramics from the tomb group found at Poggio Volpaio and the kinds of pottery found at settlement sites makes the difference clear.
So the potential of the collection from the survey for chronological studies is limited. However, the ceramics collected from systematic survey come from a broad geographical area and a wide chronological span, unlike those from a single excavation. This situation allows a consideration of aspects of the production, distribution and exchange of ceramics.