SORPTION OF GOLD FROM SOLUTION ON VARIOUS SILICAS UNDER HYDROTHERMAL CONDITIONS

Gold adsorption from dilute gold-bearing solutions on various silicas in the course of silica transformations into quartz at 150-250 degrees C and at saturation vapor pressure was studied using Au-195 tracer. T he intermediate phase SiO2-X-2 was found to play a special role in gol d accumulation on quartz. Possible mechanisms of extraction of gold fr om solution and its collection on silicas were considered. Some featur es of concurrent gold adsorption on quartz plates of various origin an d on other SiO2 species during hydrothermal treatment at 200 degrees C were concerned. The mechanism of formation of productive zones of gol d-quartz ore deposits was proposed.