Based on an interdisciplinary approach, Celtic Brass Coins project rests on an original corpus of Celtic coins which are an archaeological material of the highest value to get insight in the technology, economics and social organization of Ancient societies. Celtic Brass Coins proposes to undertake an inquiry on brass alloy at the scale of the whole Gaulish territories in order to deliver an unprecedented overview of these issues, of the monetary practices but also of the technical choices and uses to which the introduction of this new alloy in monetary economies refers. Archaeometric, numismatic, archaeological, historical and spatial data will be brought together and cross-referenced in order to place the introduction of brass within the dynamics of Celtic society and the post-conquest political landscape that is taking place in the second half of the 1st century BC. In addition to economic, monetary and technological considerations, this project is also expected to shed light on the role of the issuing authorities during the Late Iron Age, particularly at the end of the period, and on the exchange networks at the origin and/or initiated by these productions. More than 4,000 coins and 2,000 non-monetary objects will be analysed by non-destructive method in order to identify the issues concerned and to initiate a wider reflection on the introduction on the brass into the La Tène material culture. The analyses will be carried out in the most important public collections and innovative methodological developments will be undertaken at IRAMAT laboratory. The project brings together six major players in archaeometry, archaeology and in Celtic and Roman numismatics, and contributes to the affirmation of an archaeometry fully integrated into archaeological and historical issues. Celtic Brass Coins is supported by the CNRS NEMESIS International Research Network.