The Ageenkov's acheme^[1] of phase analysis of complicate copper ores hae the dieadvantages that (1) most components are not determined directly but calculated fxom a sezies of simultaneous equations, (2) some methods are based upon non-etoichiometric reactions,(3) it necessitates the use of potassium cyanide and (4) it neglects the interference of accompanying minerals, such as sphalerite,galena,pyrite etc.