Although legend has miners finding pure nuggets of the valuable mineral, most gold is found as fine grains dispersed through solid rock. To release this gold the ore must be finely ground and the gold dissolved out with reagents. Gold is the most stable element known and will react with very few chemicals . Minera Sipan mixes a slurry of ground ore and water with the finely powdered potassium cyanide in bulk bags and discharges the material into an agitated mix tank. Here the solids remain in suspension during dissolution, and oxygen is introduced to aid in the dissolving process.
Activated carbon adsorbs the dissolved gold.
Mines also undergo regular inspections by the Department of Mineral Resources and the Environmental Protection Authority to ensure compliance with regualtions. Additionally, cyanide is a high cost material and one of the largest expenses in the gold dissolving and extraction process. Minera Sipan employs stringent handling procedures and a system of containment bunds, residue disposal dams and water recycling systems, yet it had to assure a dust-free method of discharging approximately one bulk bag of material every four hours. The design protects operators from exposure to the bags' contents by firmly seating bags on the upper hopper before opening. Other bag discharge systems require the operator to open the bag before lowering into position.