The phase formation in oxide-sulphidic systems was studied with the use of X-ray diffraction, mineralography, combined thermogravimetry and calorimetry, in addition to Х-ray spectral microanalysis. The purpose of this work was to estimate the effect of cooling rate of melts in FeOx-SiO2-Cu2O-ZnO-FeS systems on structure and content of the resulting phases. Test subjects were two samples having following compositions (wt. %): I - 40.5 Fe, 2.41 S, 0.87 Cu, 3.87 Zn, 32.1 SiO2 and II - 40.7 Fe, 3.05 S, 8.55 Cu, 4.1 Zn and 19.5 SiO2. Cooling rate of the melts was changed from 0.3 up to 900оС/s.