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Sale of Esperanza Project (Details) oz in Thousands, $ in Millions |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Apr. 12, 2022 USD ($) oz | Feb. 28, 2022 USD ($) | Dec. 31, 2022 USD ($) | Mar. 31, 2022 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Disclosure of detailed information about investment property [Line Items] |  |  |  |  |  |  |
Cash and cash equivalents |  |  | $ 129.8 |  | $ 129.8 | $ 172.5 | $ 220.5
Impairment charge (note 14) |  |  |  |  | 38.2 | 224.3 |
Esperanza Milestone Payments (i) |  |  |  |  |  | 0.0 |
Milestone payment | $ 39.0 |  |  |  |  |  |
Impairment loss (reversal of impairment loss) recognised in profit or loss, after tax |  |  |  | $ 26.7 |  |  |
Consideration to be received, value |  |  |  |  | 23.0 |  |
Unrealized gain on non-hedging derivatives |  |  |  |  | $ (0.3) | $ 0.4 |
Metalla |  |  |  |  |  |  |
Disclosure of detailed information about investment property [Line Items] |  |  |  |  |  |  |
Consideration received |  |  | $ 5.0 |  |  |  |
Transaction Costs |  |  |  |  |  |  |
Disclosure of detailed information about investment property [Line Items] |  |  |  |  |  |  |
Impairment charge (note 14) |  |  |  | $ 0.2 |  |  |
Milestone One |  |  |  |  |  |  |
Disclosure of detailed information about investment property [Line Items] |  |  |  |  |  |  |
Milestone payment | $ 5.0 |  |  |  |  |  |
Number of days to receive milestone payment | 60 days |  |  |  |  |  |
Milestone Two |  |  |  |  |  |  |
Disclosure of detailed information about investment property [Line Items] |  |  |  |  |  |  |
Milestone payment | $ 14.0 |  |  |  |  |  |
Number of days to receive milestone payment | 60 days |  |  |  |  |  |
Milestone Three |  |  |  |  |  |  |
Disclosure of detailed information about investment property [Line Items] |  |  |  |  |  |  |
Milestone payment | $ 20.0 |  |  |  |  |  |
Number of days to receive milestone payment | 180 days |  |  |  |  |  |
Discontinued operations | Esperanza Project |  |  |  |  |  |  |
Disclosure of detailed information about investment property [Line Items] |  |  |  |  |  |  |
Proceeds from disposal of non-current assets or disposal groups classified as held for sale and discontinued operations | $ 21.0 | $ 60.0 |  |  |  |  |
Cash and cash equivalents | 5.0 |  |  |  |  |  |
Shares value | $ 10.0 |  |  |  |  |  |
Percentage of silver produced | 0.20 |  |  |  |  |  |
Percentage of cash price of spot silver price | 0.20 |  |  |  |  |  |
Number of ounces of silver | oz | 500 |  |  |  |  |  |

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