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v3.19.1

Other liabilities - Options under Business Combination (Details) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2018 USD ($) EquityInstruments Y shares | Dec. 31, 2017 USD ($) EquityInstruments Option Y shares | Dec. 31, 2016 USD ($) Y | Dec. 23, 2015 shares
Disclosure of terms and conditions of share-based payment arrangement [line items] |  |  |  |
Number of shares exchanged upon business combination | shares |  |  |  | 1
Share options exercised | Option |  | 30,000 |  |
Exercised during the period | Option |  | 30,000 |  |
Ferroglobe Stock Option Replacement Awards |  |  |  |
Disclosure of terms and conditions of share-based payment arrangement [line items] |  |  |  |
Share options exercised | EquityInstruments | 59,980 |  |  |
Outstanding at beginning of the period | EquityInstruments | 523,361 | 629,378 |  |
Exercised during the period | EquityInstruments | 59,980 |  |  |
Cancelled in lieu of cash settlement | shares | (191,761) |  |  |
Expired/forfeited during the period | shares |  | (71,027) |  |
Expired | EquityInstruments | (167,990) | (34,990) |  |
Outstanding at end of the period | EquityInstruments | 103,630 | 523,361 |  |
Exercisable | EquityInstruments | 103,630 |  |  |
Weighted average exercise price at the beginning of the period | $ 15.12 | $ 14.59 |  |
Weighted average exercise price, exercised | 5.89 | 6.77 |  |
Weighted average exercise price, expired/forfeited | 17.99 | 14.54 |  |
Weighted average exercise price of cancelled in lieu of cash settlement | 12.54 |  |  |
Weighted average exercise price at the end of the period | 19.40 | $ 15.12 |  |
Weighted average exercise price of share options exercisable in share-based payment arrangement | $ 19.40 |  |  |
Weighted average remaining contractual term, outstanding | Y | 0.44 | 0.89 | 1.75 |
Weighted average remaining contractual term, exercisable | Y | 0.44 |  |  |
Aggregate intrinsic value of options outstanding |  | $ 1,774,000 | $ 580,000 |
Number of options vested | shares | 103,630 | 515,028 |  |
Number of options unvested | shares |  | 8,333 |  |
Share based compensation expense | $ 287,000 | $ 4,000 |  |
Payment settled for equity shares | $ 680,000 |  |  |

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