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v3.22.4

Financial Instruments and Risk Management (Fair Value for Assets and Liabilities) (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Disclosure of fair value measurement of assets [line items] |  |
Financial assets (liabilities) | $ (3,674.2) | $ (3,621.5)
Financial liabilities | 953.1 | 885.9
Esperanza Milestone Payments (i) |  | 0.0
Assets held for sale (note 14) | 5.0 | 0.0
Total financial instrument exposure to credit risk | $ 153.5 | 176.5
Discount rate, milestone payments | 0.0912 |
Profit (loss) before tax | $ 102.4 | 2.3
Change in Assumptions, Effect |  |
Disclosure of fair value measurement of assets [line items] |  |
Profit (loss) before tax | 2.5 |
Concentrate Receivable [Member] |  |
Disclosure of fair value measurement of assets [line items] |  |
Total financial instrument exposure to credit risk |  | 0.0
Level 1 | Recurring fair value measurement |  |
Disclosure of fair value measurement of assets [line items] |  |
Fair value, net asset (liability) | 18.6 | 23.9
Level 2 | Recurring fair value measurement |  |
Disclosure of fair value measurement of assets [line items] |  |
Fair value, net asset (liability) | (4.2) | 3.5
Level 3 | Recurring fair value measurement |  |
Disclosure of fair value measurement of assets [line items] |  |
Fair value, net asset (liability) | 24.1 |
Esperanza Milestone Payments (i) | 19.1 |
Assets held for sale (note 14) | 5.0 |
Derivatives |  |
Disclosure of fair value measurement of assets [line items] |  |
Financial assets, at fair value | (4.3) | 3.0
Derivatives | Gold Options |  |
Disclosure of fair value measurement of assets [line items] |  |
Financial liabilities, at fair value | (0.1) |
Financial assets, at fair value |  | 0.5
Derivatives | Currency Hedging Derivative Instruments |  |
Disclosure of fair value measurement of assets [line items] |  |
Financial liabilities, at fair value | 4.3 |
Financial assets, at fair value |  | 2.6
Derivatives | Fuel Options |  |
Disclosure of fair value measurement of assets [line items] |  |
Financial assets, at fair value | 0.0 | 0.4
Fair value through profit or loss | Gold Options | Level 2 | Recurring fair value measurement |  |
Disclosure of fair value measurement of assets [line items] |  |
Financial liabilities | 0.1 | 0.5
Fair value through OCI | Currency Hedging Derivative Instruments | Level 2 | Recurring fair value measurement |  |
Disclosure of fair value measurement of assets [line items] |  |
Financial liabilities |  | 2.6
Fair value through OCI | Fuel Options | Level 2 | Recurring fair value measurement |  |
Disclosure of fair value measurement of assets [line items] |  |
Financial liabilities |  | 0.4
Fair value through OCI | Trading securities | Level 1 | Recurring fair value measurement |  |
Disclosure of fair value measurement of assets [line items] |  |
Financial assets (liabilities) | $ (18.6) | $ (23.9)

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