An inventory of the copper-based metal objects of the megalithic necropolis of Sion/Petit-Chasseur has been compiled. 52 objects (or groups of objects) attributed to the Late Neolithic (Néolithique final valaisan), the Bell Beaker period and the Early Bronze Age have been identified. The inventory is completed by new analyses of the chemical composition undertaken for a sub-group of in total 27 lead isotope analyses and 35 chemical analyses in addition to the two lead isotope analyses and eleven chemical analyses already published. The results highlight that several sources of supply were used between the third millennium and the first half of the second millennium BC. With regard to the Late Neolithic period in Valais, the available data do not allow to determine whether copper ore or metal was used for the manufacturing of the tubular beads discovered in monument M XII of Sion/Petit-Chasseur III. A copper awl with a terminus ante quem at the beginning of the Early Bronze Age presents a chemical composition found again in the Late Neolithic of the Swiss Plateau. Although different possible sources can be taken into account at the European scale (Germany, Austria, Spain, Serbia), the prehistoric mine of Saint-Véran (Hautes-Alpes, France) is the closest one. The analyses of two pieces of the Early Bronze Age BzA1 (2200-2000 BC) reveal a quite particular copper known as “Singen type composition”. Though the lead isotope ratio measurements do not permit to identify the origin of the metal, they nonetheless indicate that these two artefacts are part of a network of raw material procurement, similar to the northern Alpine area evidenced by the site of Singen (Germany). With the start of the Early Bronze Age BzA2 (2000-1550 BC), the change of copper sources is accompanied by a technical evolution, the introduction of bronze technology. From that period on, supply of Valaisian copper cannot be excluded for most of the objects. However, lead isotope variation of local mineralisation is little specific and overlays many other European mineralisation patterns being also possible sources for this metal. An extraneous source, in the coastal part of Southern Tuscany, has been identified for one object. Five further other objects are possibly stemming from a blending of ores from the southern coast of Tuscany and other unidentified sources. Concerning the BzA2 period, the graves 2 and 3 of Sion/Petit-Chasseur I raise the question of the manufacturing of personal equipment. The grave goods deposited together with the buried individuals show homogeneous compositions, hardly compatible with progressive and random development of a personal equipment, but would rather mirror that they have been constituted during a short period of time, within a project.