"This multidisciplinary project comprising archaeology, history, geochemistry, and geology aims at the decipherment of the enigma of the origin of a material that emerged in the third millennium BCE and gave an entire cultural epoch its name, namely the alloy of copper and tin called bronze. While copper deposits are relatively widely distributed there are only very few tin deposits known in the Old World (Europe, the Mediterranean basin and southwest Asia). Since the late 19th century archaeologists have discussed the question of the provenance of tin for the production of the earliest bronzes without any definite answer. The enigma has even grown over the past decades, because it turned out that the earliest bronzes appear in a wide area stretching from the Aegean to the Persian Gulf that is geologically devoid of any tin deposits. There is tin in western and central Europe and there is also tin in central Asia. Thus, tin or bronze seems to have been traded over large distances but it is unknown in which direction.Now a new method has become available that offers the chance to trace ancient tin via tin isotope signatures. It was found that the isotope ratios of tin exhibit small but measurable variations in nature making different tin deposits identifiable so that bronze objects can in principle be related to specific ore deposits. It is proposed to apply for the first time this new technology to characterize all known tin deposits in the Old World and relate them to bronze and tin artefacts of the third and second millennia BCE. This groundbreaking interdisciplinary study will increase our understanding of Bronze Age metal trade beyond surmise and speculation with vast implications for the reconstruction of socio-economic relations within and between Bronze Age societies. The impact will be a major advance in our understanding of the earliest complex societies with craft specialization and the formation of cities and empires."