Would an eighth century Umayyad ship bringing grain from Tunis to Alexandria use amphorae? What about an 11th century Neapolitan trade ship going from southern Italy to Spain?
In visiting a number of small, local museums in south west France this year I have been surprised at the medieval persistence of amphorae, something which is distinctly 'Roman' in my mind. Samples I saw were dated right through the 13th century. These would be finds in the western Mediterranean littoral through to Toulouse.
A quick search turned up this archaeology report of a dig in eastern Europe that dates amphorae found from 9th to 14th centuries of Byzantium. Cursorily reading the arguments it seems amphorae were distributed and traded on Black Sea and across the Mediterranean for much of the medieval period.
The report further suggests that graffiti on the vessels suggests merchants writing and overwriting content codes and which in turn suggests reuse for various items. The French museum specimens were claimed as wine and olive oils vessels.