In our previous experiment RB 1810171 we analysed a group of three Japanese swords from an important private collection. Among the samples included in the proposal, we found many unusual aspects related to their forging and microstructures, since these results enabled us to allow a clear identification of their microstructures and phase compositions and to relate them to the different treatments applied to the swords. We hope to go on with this research by analysing another small group of swords which belong to the same collection and which visual inspection suggests may have different microstructures and so to try to identify the possible methods used to forge them. We propose to measure the composition and microstructural properties in different selected cross-sections of the blades, to characterize the quality of the metal and the thermal and mechanical treatments applied.