The Chemical Study of European Brass Tokens

6 THE CHEMICAL STUDY OF EUROPEAN BRASS TOKENS AND COINS 

The Oxford University Research Laboratory for Archaeology and the History of Art has had a long-standing interest in the analysis of metals. An example of 

The technological information derived from a study of the early jettons can be summarized quite simply - before ca. AD 1450, European jettons contained on average around 4% tin and 1-2% lead, with a low zinc content, typically less than 10%. Traces of antimony, silver and arsenic are often present at 0.1- 02%. Nickel is very low, usually less than 0.05%. After AD 1450, the zinc content rises quickly to over 20%, with a corresponding fall in the lead (less than 1%) and tin (less than 0.2%). The trace elements are usually less than 0.1%, with the exception of nickel, present up to 0.5%. The combined copper plus zinc total is usually greater than 97%. 

There is probably a twofold explanation for this change during the 15th Century. One is a change in the copper ore source that supplied much 

showing an average Ni content of 0.036%, with 0.16% As and 0.13% Sb. Although far from conclusive, these analyses suggest that the characteristics observed in the jettons do indeed reflect a change in the copper in circulation from sources in Sweden to somewhere in central Europe, some time around AD 1450. 

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