Probing the elemental composition of thin-film layers with non-destructive methods is a serious challenge that has not yet a real answer. Negative muons have this capability, despite their limitation coming from the difficulties of implanting in materials having small volumes.Within this explorative proposal, we will develop the technique by measuring several multilayers of transition metals with grazing incidence experimental conditions. We will change the relative orientation of sample surface and incoming beam, and the collection of muonic X-rays following the muon implantation will reveal the feasibility of studies with this technique to measure the elemental composition of materials in the form of thin films.