3_Figure (IMAGE) Aarhus University Caption The lead isotope plot of the over 65 shafthole axes analyzed in this study dating to the end of the first Bronze Age period 1600 BC. This amount of data exceeds the previous analyses by ten times and for the first time allows to compare both axe types and understand their development. Credit No credit Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.