3.9 Intangible assets
Intangible assets with finite useful lives, acquired separately, are carried at cost less accumulated amortization and accumulated impairment losses, if any.
The method of amortization of Mining exploitation rights will be determined at the time it become used by the Company.
The estimated useful life and amortization method are reviewed at the end of the fiscal year, with the effect of any changes in estimate being accounted for on a prospective basis. Intangible assets with indefinite useful lives, acquired separately, are carried at cost less accumulated impairment losses.
Derecognition of intangible assets
An intangible asset is derecognized on disposal, or when no future economic benefits are expected from use or disposal. Gains or losses arising from derecognition of an intangible asset, measured as the difference between the net disposal proceeds and the carrying amount of the asset, are recognized in profit or loss when the asset is derecognized.