Adsorption of diethyldithiocarbamate and ethylxanthate on chalcopyrite mineral surface was studied by static bed adsorption method. The qualitative nature of surface species was examined by selective solvent extraction and UV-visible spectroscopic technique. The results clearly indicate that the interaction between surface metal ions and thiols is chemical in nature. As a result of chemical interaction of ligand molecules, metal ions from mineral surface are dislodged from the lattice and precipitates of metal-ligand complexes were formed on the surface, Surface complexes were found to be identical to that of bulk complexes with metal-to-ligand ratio of 1:2.