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Critical Accounting Estimates and Judgements | 12 Months Ended
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Dec. 31, 2017
Disclosure of notes and other explanatory information [Abstract] |
Critical Accounting Estimates and Judgements |
4. | CRITICAL ACCOUNTING ESTIMATES AND JUDGEMENTS
Many of the amounts included in the Consolidated Statements of Financial Position require management to make estimates and judgements. Accounting estimates and assumptions are continually evaluated and are based on historical experience and other factors, including expectations of future events that are believed to be reasonable under the circumstances. Revisions to accounting estimates are recognized in the period in which the estimates are revised. Critical accounting estimates The following is a list of the accounting estimates that the Company believes are critical, due to the degree of uncertainty regarding the estimates or assumptions involved and the magnitude of the asset, liabilities, revenue or expense being reported. Actual results may differ from these estimates.
• | The Company accounts for its ore stockpiles and in-process precious metals inventory using a process flow for applicable costs appropriate to the physical transformation of ore through the mining, crushing, leaching from heap leach operations, milling and gold recovery process. The Company estimates the expected ultimate recovery based on laboratory tests and ongoing analysis of leach pad kinetics in order to estimate the recoverable metals at the end of each accounting period. If the Company determines at any time that the ultimate recovery should be adjusted downward, then the Company will adjust the average carrying value of a unit of metal content in the in-process inventory and adjust upward on a prospective basis the unit cost of subsequent production. The Company estimates concentrate production based on assays and moisture samples taken and tested in laboratories, as well as weights using a calibrated scale. Final weights and assays are taken on settlement with the buyer, which are reconciled to production. Should an upward adjustment in the average carrying value of a unit of metal result in the carrying value exceeding the realizable value of the metal, the Company would write down the carrying value to the realizable value.
• | The Company values inventory at the lower of cost and net realizable value. The calculation of net realizable value relies on forecasted gold prices, estimated grades of ore on stockpiles, concentrate and heap leach pads, forecasted exchange rates, and estimated costs to complete the processing of ore inventory.
• | The Company makes estimates of the quantities of proven and probable reserves of the mine and the portion of mineralization expected to be classified as reserves. The estimation of quantities of reserves and resources is complex, requiring significant subjective assumptions that arise from the evaluation of geological, geophysical, engineering and economic data for a given ore body. This data could change over time as a result of numerous factors, including new information gained from development activities, evolving production history and a reassessment of the viability of production under different economic conditions. Reserve estimates are used in the calculation of depletion expense and to calculate the recoverable amount of a CGU, and to forecast the life of the mine.
• | The Company forecasts prices of commodities, exchange rates, production costs, discount rates, and recovery rates. These estimates may change the economic status of reserves and may result in reserves and resources being revised. In addition, these estimates are used to calculate the recoverable amount of a CGU for the purpose of impairment testing.
• | The Company amortizes its property, plant and equipment, net of residual value, over the estimated useful life of each asset, not to exceed the life of the mine at which the asset is utilized. The Company uses estimated proven and probable mineral reserves, and an estimate of mineral resources as the basis for amortizing certain mineral property, plant and equipment. The physical life of these assets, and related components, may differ from the Company’s estimate, which would impact amortization and depletion expense.
• | The Company makes estimates of the likelihood of whether or not all or some portion of each deferred income tax asset and investment tax credits will be realized, which is impacted by interpretation of tax laws and regulations, historic and future expected levels of taxable income, timing of reversals of taxable temporary timing differences, and tax planning initiatives. Levels of future taxable income are affected by, among other things, market gold prices, production costs, quantities of proven and probable gold reserves, interest rates, and foreign currency exchange rates.
• | The Company makes estimates of the timing and amount of expenditures required to settle the Company’s decommissioning liabilities. The principal factors that can cause expected future expenditures to change are: the construction of new processing facilities; changes in the quantities of material in reserves and a corresponding change in the life of mine plan; changing ore characteristics that ultimately impact the environment; changes in water quality that impact the extent of water treatment required; and changes in laws and regulations governing the protection of the environment. In general, as the end of the mine life nears, the reliability of expected cash flows increases, but earlier in the mine life, the estimation of a decommissioning liability is inherently more subjective.
Critical accounting judgements The following are critical judgements that management has made in the process of applying accounting policies that may have a significant impact on the amounts recognized in the consolidated financial statements.
• | The Company makes judgements about whether or not indicators of impairment, or indicators of a reversal of impairment, exist at each reporting period. This determination impacts whether or not a detailed impairment assessment is performed at the reporting date. These judgements did not impact cash generating units at December 31, 2017, or for December 31, 2016.

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- Definition The disclosure of judgements that management has made in the process of applying the entity's accounting policies that have the most significant effect on amounts recognised in the financial statements along with information about the assumptions that the entity makes about the future, and other major sources of estimation uncertainty at the end of the reporting period, that have a significant risk of resulting in a material adjustment to the carrying amounts of assets and liabilities within the next year. [Refer: Carrying amount [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 10 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_10_e&doctype=Standard -URIDate 2017-03-09 + Details
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