Castel-Minier, located in the French Pyrenees, was a polymetallic production site where silver, lead and copper using ores extracted on-site and from neighbouring valleys were produced by metallurgists from the 13th to 15th centuries. Through necessity and opportunism, they also produced iron for export and on-site use. The archaeological excavations carried out over the last twenty years have brought to light a series of tools associated with mining, including chisels, which are emblematic tools of miners. These chisels represent rare specimens in Western Europe for this period and are the only ones discovered in the French Pyrenees. We describe these discoveries and then focus on the chisels to highlight the durability and variability of the manufacturing methods of these tools. Indeed, different skills have been used on the site.