iodine in the elemental form the halogenated salts which are effectively usable in the method of this invention include halogenated quaternary nitrogen compounds and halogenated metal salts for example the halogenated quaternary nitrogen compounds are the compounds represented by the general formula str1 wherein r 1 r 2 r 3 and r 4 independently stand for a hydrogen atom or a hydrocarbon group of 1 to 18 carbon atoms provided that two or more of these substituents jointly form a ring and x stands for a chlorine ion a bromine ion or an iodine ion to be specific these compounds include halogenated ammonium salts such as ammonium chloride halogenated hydrogen salts of primary secondary and tertiary amines such as methylamine hydrochloride dimethylamine hydrobromide and trimethylamine hydrobromide and halogenated quaternary ammonium salts such as tetramethylammonium bromide and cetylpyridinium bromide for example as halogenated metal salts halogenides of alkali metals and alkaline earth metals prove to be particularly suitable potassium bromide sodium iodide and calcium bromide are concrete examples the elemental halogen and the halogenated salt are both required to be used in an amount of not less than an equimolar amount relative to the amount of gold and silver in the ore to heighten the ratio of extraction they.