The Museum of Antiquities preserves numerous protohistoric brooches (fibulae) with disc stirrup, coming from the nineteenth-century collection of Giovanni Battista Assi. The whole makes it possible to observe all the steps in the evolution of the production technique of the stirrup thus conformed, from the final Bronze Age (11th century BC) to the early Iron Age (8th century BC). The most significant step is the change in the preparation of the pre-finished product and the procedure for making the spiral. Initially it is a simple winding for decorative purposes of the end of the circular section wire with which the fibula is made. The specimens in which a hammering action performed vertically on the already wound wire spiral still dates back to the final Bronze Age. In the immediately following specimens, the hammering will instead be carried out during the winding phases, so that the characteristic spiral shape with an asymmetrical spiral results. The end from which the disc is obtained, at the pre-processed level, consists of a rod obtained by casting in the shape of a flattened cigar, gradually wound and repeatedly hammered, with annealing steps. This new typology had to meet particular favor due to the possibility of exploiting the smooth surface to accommodate decorative elements engraved with a metal punch or engraved with a metal stylus tip or hand-grained stone. This aesthetic requirement finds further development with the choice of creating a solid disc without discontinuity, obtained by the crushing of a ball-like enlargement, on which the compositional schemes can be enriched and diversified since they are now freed from a spiral-shaped support. At this point the disc can also be made separately and then fixed to the fibula with rivets, probably to obviate the frequent breakages in the hammering phase of the attachment area between the bracket and the pin holder.