  The ED-XRF (Energy-Dispersive X-ray Fluorescence) measurements and the FLUKA
simulations have been made to discuss the possibility of recognition of coating
layer as well as to its thickness measurement. In this work the
$I_{K\alpha}$(Cu)/$I_{K\alpha}$(Ag) intensity ratios as well as
$I_{K\beta}$(Ag)/$I_{K\alpha}$(Ag) and $I_{K\beta}$(Cu)/$I_{K\alpha}$(Cu) for
copper samples coated with various thickness of sputtered silver have been
analyzed. The results show strong dependence of these factors with coating
silver layer thickness. The measurements show the performance of this method in
archaeometry. Since the use of non-destructive methods during tests on ancient
silver artifacts may not supply to obtain reliable bulk results and should be
considered applicable for only surface analyses, the measured intensity ratios
can be applied as a tool to estimation of surface silver enrichment thickness.
