Computer simulations of apatite thin films at a range of quartz surfaces have shown how the strength of adhesion between thin films of apatite material and ceramic silica surfaces is crucially dependent upon both the orientation of the film relative to the substrate and the nature of the silica surface-a finding that is important in a wide number of applications, from basic geological research on intergrowth of phosphate and silicate rock minerals to the search for more effective surgical implant materials.