Gold and silver are extracted from their native ores by,
Leaching is often used if the ore is soluble in some suitable solvent. In the metallurgy of silver and gold, the respective metal is leached with a dilute solution of NaCN or KCN in the presence of air, which supplies O 2 . The metal is obtained later by replacement reaction.Cyanide Gold Extraction Process - JXSC Machine,Cyanide gold extraction process, the process of extracting gold with cyanide is called cyanidation gold extraction, which is the main method for extracting gold from ore or concentrate.. Basic Gold Cyanide Process Steps. The cyanidation gold extraction process includes cyanide leaching, washing and leaching of the leaching slurry, extraction of gold from the cyanide or cyanide slurry, and,Gold: Occurrence, principles of extraction, Properties and,,iii) Treatment with KCN . The finely powdered roasted ore is taken in large vats made up of cement or iron and having false wooden bottoms with holes. It is then treated with a dilute (0.5%) solution of KCN in presence of excess of air for 24 hours. As a result, gold dissolves in KCN to form a soluble complex called potassium aurocyanide.