Inventories - Summary of Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Disclosure Of Inventories [Abstract]
Ore in process	$ 16,764	$ 6,347
Finished metal inventory	383
Supplies	4,837	3,988
Current inventories	$ 21,984	$ 10,335

Disclosure of inventories.

No definition available.

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A classification of current inventory representing the amount of goods that have completed the production process and are held for sale in the ordinary course of business. [Refer: Inventories]

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The amount of current inventories. [Refer: Inventories]

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A classification of current inventory representing the amount of supplies to be used for the production process. [Refer: Inventories]

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A classification of current inventory representing the amount of assets currently in production, which require further processes to be converted into finished goods or services. [Refer: Current finished goods; Inventories]

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