THE COMPOSITION OF IRON AGE STRUCK 'BRONZE'COINAGE IN EASTERN ENGLAND

EDXRF was used to analyse the composition of 88 Iron Age copper and copper alloy coins excavated from the site of a pre-Roman shrine and Roman temple at Harlow, Essex. Most of the coins are local to the Essex-Hertfordshire region, with a few of Kentish origin. The earliest struck base metal issues were struck from almost pure copper, but from the late first century BC, their composition shows more variety. Particularly interesting are a group of types belonging to the Romanizing phase of Tasciovanus'coinage, which were struck in brass and possibly represent a distinct denomination. Roman coinage and other metalwork imports from the Roman world presumably provided the initial impetus, and the ultimate source of the brass. However, this experiment was relatively short lived. Cunobelinus, who ruled eastern England during the earlier first century AD, mainly employed bronze to strike his abundant base metal coinage. The products of his Colchester mint reveal a consistently different composition from those struck at his unlocated second mint in the Hertfordshire area, although the precise alloy does vary, sometimes within the same type. This suggests that unlike gold and silver issues, the source and purity of the metal used for minting base metal coinage was not always critical.