Stacking crushed ore on a lined pad and trickling solution through it to dissolve the metal — low cost, low recovery.
An industrial mining process used to extract precious metals from ore by placing crushed ore in large heaps and percolating a chemical solution through it to dissolve the valuable minerals. This method is economical for processing lower-grade ore deposits and is commonly used in gold mining operations.
Heap leaching makes low-grade oxide deposits economic that no mill could justify. Capital cost is a fraction of a conventional plant, which is why it is often the route a junior can actually finance.
Recoveries are typically far below milling, and leach kinetics can take months. A heap leach project's economics depend heavily on how much metal is recovered within the modelled leach cycle.
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