Thanks for your suggestion. There is gold gold concentrate with gold grade 25.20g/t and the contents of organic carbon 27% and mostly of the gold minerals are packed by pyrite, arsenopyrite and gangue. I need to determine the gold content of bareness, gold exact content of carbon, gold exact content of packed by pyrite and arsenopyrite, respectively. When i use specifically reagent to extract the bareness gold which is easy to be absorbed by carbon. I could not find a good way to do. I need you help. Thanks very much.