Derivative instruments (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
DERIVATIVE LIABILITIES
Total derivative liabilities	$ 0.9	$ 26.2
Unsettled provisionally priced concentrate derivatives, and swap contracts
DERIVATIVE LIABILITIES
Total derivative liabilities	0.9	(0.2)
Gold price option contracts
DERIVATIVE LIABILITIES
Total derivative liabilities	$ 0.0	$ 26.4

The amount of financial liabilities classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_55&doctype=Standard
-URIDate 2020-01-01

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