L'hétérogénéité des teneurs en plomb dans les monnaies de bronze antiques

The lead contents can vary greatly in a series of bronze coins belonging to a same type. This variation maybe due to changes in the bronze composition or to lead segregation during the casting process. A limestone mould for casting bronze blank was discovered at the Gallic-Roman site of Châteaubleau (France) and was used as a starting point to study lead segregation in bronze blanks. Bronze blanks were cast in a modern mould similar to the one found at Châteaubleau using ancient methods. Our experiments show that the variation in lead contents of the blanks is random.