When we ask ourselves what is the structure of polypeptide/crystal interfaces in the context of either materials recognition by oligopeptides or of protein-controlled mineralization, we may have in mind a rather static picture with atoms occupying ordered positions, as obtained for instance by diffraction experiments. However, on the one hand biomineralization often proceeds via the initial formation of disordered inorganic precursors, which are converted to crystalline phases only at a later stage. On the other hand, peptides that recognise and bind specifically to crystalline oxide facets mostly present a disordered ensemble of secondary structures. This makes a characterization of the atomic-level details of such interfaces very challenging both for experiments and for simulations. In this talk I will present results of our investigations into the precipitation of FeOx(OH)y, as induced for instance by ferritin proteins, and into ZnO-binding peptides interacting with ZnO crystals in liquid environments. Our goal is to attempt to find ordered patterns within the disordered structures and conformational ensembles by a combination of all-atom molecular dynamics simulation with atomic-force microscopy and circular dichroism spectroscopy.