Inventories - Summary of Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Inventories [Abstract]
Stockpile	$ 688
Ore in process	61,612	$ 16,764
Finished metal inventory	4,883	383
Supplies	4,196	4,837
Total inventories	71,379	21,984
Less: non-current ore in process	7,081
Current portion	$ 64,298	$ 21,984

Disclosure of inventories.

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A classification of current inventory representing the amount of ore stockpiles. [Refer: Inventories]

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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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The amount of assets: (a) held for sale in the ordinary course of business; (b) in the process of production for such sale; or (c) in the form of materials or supplies to be consumed in the production process or in the rendering of services. Inventories encompass goods purchased and held for resale including, for example, merchandise purchased by a retailer and held for resale, or land and other property held for resale. Inventories also encompass finished goods produced, or work in progress being produced, by the entity and include materials and supplies awaiting use in the production process. [Refer: Current finished goods; Current merchandise; Current work in progress; Land]

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A classification of non-current inventory representing the amount of ore stockpiles. [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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