Carbon can be present as carbonate mineral and inorganic material. The last one ranges from graphite, which is a poison from a treatment consideration, to the named carbonaceous matter that has near of eighty percent of carbon and consists of active element carbon, hydrocarbons and organic acids. This type of carbon is problem when the ore must be treated by cyanidation due to cause the called effect of pre-robbing. This phenomenon consists in absorbs the free cyanide and gold cyanide complex from cyanide leach solutions. This situation is found in Witwatersrand ores and there is association between organic matter, uraninite and gold. Try to treat this ore is complex and needs more than one process in order to recover gold.