Experimental modeling of zonality of copper-rich sulfide ores in copper-nickel deposits

To model the formation of the zonal structure of copper-rich sulfide Cu-Ni ores of the Norilsk type, a sample composed of 35.6 of Fe, 14.0 of Cu, and 50.0 at.% of S with an admixture of 0.05 at.% of each of Pt, Pd, Rh, Ir, Au, Ag, and Mo is subjected to directional crystallization. The crystallized ingot consisted of three parts: (1) a pyrrhotine solid solution (PSS), (2) a poss-and-cubanite mixture, and (3) an intermediate solid solution (ISS). Curves of the ore component distribution in the sample are plotted; their coefficients of distribution (k) between the solid solutions and the sulfide melt are measured. It is shown that admixtures of Rh, Ru, and Ir concentrate in PSS, and the other admixtures form their own minerals mainly associated with ISS. Coefficients k of Ru, Rh, and Ir are determined between the PSS and the sulfide melt. The results of the sample crystallization presented in the paper satisfactorily imitate natural zonality of low-sulfur copper sulfide ores. Previously, it was shown that directional crystallization of the sample of CuFeS2 composition imitates the zonality of highsulfur ore bodies in Norilsk deposits. Thus, we proved the application perspective of directional crystallization for modeling features of forming copper-rich sulfide ores.