A major climatic shift, from a glasshouse world to a colder climate with well-developed ice sheets, occurred during the Cenozoic. Such a transition is recorded in both marine and terrestrial records. The latter is more fragmentary and thus comparatively less well known from a climatic point of view. Leaves are abundant fossil remains, which can be used as terrestrial climatic proxies. In this study, several historical collections from France and Belgium were re-investigated. We applied the Climate Leaf Analysis Multivariate Program in order to document the regional past climate from middle Paleocene to middle Miocene in Western Europe. Our analysis suggest relatively cooler conditions during middle Paleocene, followed by a gradual increase of mean annual temperature and precipitation seasonality during late Paleocene; increased temperature seasonality rather than a global cooling at the Eocene-Oligocene transition; an increase of temperature between early and late Oligocene and warm temperate climate in Western Europe similar to other parts of Europe during middle Miocene. These results are broadly consistent with the global trends observed through the Cenozoic era in the marine record. This study provides new quantitative paleoclimatic estimates for various key periods of the Cenozoic era in Western Europe. The consistency of our results with previous studies based on multiples proxies is in favor of the use of historical collections to reconstruct past climates, as long as sufficient sampling is provided. RÉSUMÉ Évolution du climat en Europe occidentale durant le Cénozoïque : apports des collections historiques à travers l'utilisation de la morphologie foliaire. Durant le Cénozoïque, une transition majeure d'un climat chaud et humide vers un climat plus froid avec des calottes glaciaires bien développées, est observée. Cette transition est documentée dans les registres fossiles marin et continental. En raison de la nature plus fragmentaire de ce dernier, les conditions climatiques continentales sont comparativement moins bien connues. Parmi les restes de plantes conservées dans les sédiments, les feuilles sont particulièrement abondantes et peuvent être utilisées comme proxy climatique terrestre. Dans cette étude, plusieurs collections historiques de France et de Belgique ont été réétudiées. La méthode Climate Leaf Analysis Multivariate Program a été appliquée, afin de documenter le climat régional du Paléocène moyen au Miocène moyen en Europe occidentale. Notre analyse suggère des conditions climatiques relativement fraîches pendant le Paléocène moyen, suivies d'une augmentation graduelle de la MAT et de la saisonnalité des précipitations au cours du Paléocène supérieur, une saisonnalité accrue plutôt qu'une baisse de la MAT à la transition Eocène-Oligocène, une augmentation des températures au cours de l'Oligocène et un climat tempéré chaud semblable au reste de l'Europe durant le Miocène moyen. Dans l'ensemble, ces résultats sont cohérents avec les tendances globales observées au cours du Cénozoïque dans le ...

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The Valaisan-type armband (a specific type of bracelet) is a typical metallurgical production from the western area of Switzerland belonging to the classic phase of the Aare-Rhone group (BzA2a, ca. 2000–1800 BC). This investigation aims to (i) characterize the metal composition, (ii) reconstruct the thermomechanical treatments applied during the manufacturing process, and (iii) gather information on the possible exploitation of the local ores coupling metallography and chemical analysis. The results show that each armband is manufactured from a hammered sheet of copper-based alloy, containing either tin (up to 3.0 wt.%) or a combination of antimony, nickel, and silver. In several cases, it is assumed that minor elements are already part of the original ore, suggesting a conscious selection of copper veins. In other armbands, a direct addition of cassiterite (SnO2) to the copper matrix is hypothesized based on the material composition and features of the inclusions. Microstructural features are coherent with a procedure that combines mechanical deformation (with a total deformation degree between 70 and 76%), annealing, and quenching, coherently with more recent productions (Late Bronze Age). The analysis of inclusions, rarely performed during metallographic investigations, provides precious evidences on thermal treatments applied during the manufacturing process and shows that annealing was carried out at low temperatures.