Crystallization Of Platinum In Self-crystallizing Hydro Thermal Systems

摘要

Several deposits with hydrothermal platinum mineralization have been discovered in recent years . Study of such deposits requires data on the mass transfer of Pt by hydrothermal solutions and geochemical barriers that are favorable for its precipitation. Therefore, we studied Pt solubility in complex S- and As-bearing fluids at 300-500℃ and P_(tot) = 1 kbar . The results indicated that the presence of S and As in natural hydrothermal solutions fosters the precipitation of platinum sulfides and arsenides even from Pt-poor solutions. Moreover, the process of crystallization is accompanied by the generation of intermediate stable complexes and their disproportionation into sperrylite and cooperite. However, experimental data on the crystallization of native platinum in hydrothermal solutions are absent thus far.