Purpose: The aim of the investigations is the formation of electrolytic extractions from Cu-Zr and Cu-Ce model alloys containing microadditions of Zr and Ce amounting to about 0.1% by weight and their identification by X-ray diffraction analysis. Design/methodology/approach: Electrolytic extractions were obtained by the anodic dissolution of the alloys. In the X-ray analysis the comparative method was applied. Findings: The activity of anodic dissolution of the investigated alloys was determined basing on the mass of the electrolytic extraction and the time of dissolution of the alloy in solutions of the electrolytes with different chemical compositions and a different complexive effect to copper and different pH. Research limitations/implications: The qualitative X-ray phase analysis permits to identify the main intermetallic phases of the investigated alloys in a limited range, mainly due to experimental reasons. Practical implications: The results of these investigations indicate a distinct relation between the mass and the kind of the dissolved phase and the value of the electrochemical potential of the active dissolution of the alloys. Originality/value: The revealing of this relation is of practical importance in regard to the accuracy of the results of the phase and crystal analysis carried out by X-ray diffraction examination.