· With cyanide leaching, gold extraction could be increased from 55 ‒ 65%–90% (Marsden and House, 2006; Habashi, 2005). Later cyanide leaching has been operated in various modes heap leaching, CIP (carbon in pulp), CIL (carbon in leach), and RIP/RIL (resin in pulp/leach) (Marsden and House, 2006). The environmental hazards and toxicity of cyanide have increased the interest in a new ...