Write downs of ore in stockpiles ore on leach pads in

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Unformatted text preview: and accumulated as the cost of ore in stockpiles, ore on leach pads, in-process and finished metal inventories. These deferred amounts are carried at the lower of average cost or NRV. Write-downs of ore in stockpiles, ore on leach pads, in-process and finished metal inventories resulting from NRV impairments are reported as a component of current period costs. The primary factors that influence the need to record write-downs include prevailing and long-term metal prices and prevailing costs for production inputs such as labour, fuel and energy, materials and supplies, as well as realized ore grades and actual production levels. Costs are attributed to the leach pads based on current mining costs, including applicable depreciation, depletion and amortization relating to mining operations incurred up to the point of placing the ore on the pad. Costs are removed from the leach pad based on the average cost per recoverable ounce of gold on the leach pad as the gold is recovered. Estimates of recoverable gold on the leach pads are calculated from the quantities of ore placed on the pads, the grade of ore placed on the leach pads and an estimated percentage of recovery. Timing and ultimate actual recovery percentage of gold contained on leach pads can vary significantly from the estimates. The quantities of recoverable gold placed on the leach pads are reconciled to the quantities of gold actually recovered (metallurgical balancing), by comparing the grades of ore placed on the leach pads to actual ounces recovered. The nature of the leaching process inherently limits the ability to precisely monitor inventory levels. As a result, the metallurgical balancing process is constantly monitored and the engineering estimates are refined based on actual results over time. The ultimate actual recovery percentage of gold from a pad will not be known until the leaching process is completed. The allocation of costs to ore in stockpiles, ore on leach pads and in-process inventories and the determination of NRV involve the use of estimates. There is a high degree of j...
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This document was uploaded on 03/30/2014.

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