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v3.19.1

Identification and business activity (Details 2) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Operating income |  |  |
Net sales | $ (1,122,995) | $ (1,223,942) | $ (1,015,670)
Total income | (1,167,381) | (1,274,378) | (1,068,791)
Operating costs |  |  |
Cost of sales, excluding depreciation and amortization | 982,957 | 980,254 | 824,973
Depreciation and amortization | (241,286) | (213,722) | (192,647)
Mining royalties | (21,526) | (31,217) | (27,611)
Total operating costs | (982,957) | (980,254) | (824,973)
Gross loss | (184,424) | (294,124) | (243,818)
Operating income (expenses), net |  |  |
Reversal of Impairment loss of long-lived assets, note 11(b) | 0 | 11,770 | 0
Administrative expenses | (78,760) | (83,597) | (81,692)
Impairment loss of long-lived assets |  | (21,620) | 0
Others, net | 68,683 | 258,826 | 24,107,000
Total operating expenses, net | (130,669) | (188,608) | (111,622)
Operating loss | (53,755) | (105,516) | (132,196)
Other income (expense), net |  |  |
Finance costs, note 15(b) | (38,456) | (34,623) | (31,580)
Net gain (loss) from currency exchange difference | 1,366 | (2,928) | (2,638)
Total other expenses, net | (31,280) | (12,971) | (387,433)
Loss before income tax | (7,203) | (10,098) | (19,069)
Loss from discontinued operations | 7,203 | 10,098 | 19,073
Discontinued Operations Mining Activities [Member] |  |  |
Operating income |  |  |
Net sales | 0 | 0 | 1,149
Total income | 0 | 0 | 1,149
Operating costs |  |  |
Cost of sales, excluding depreciation and amortization | 0 | 0 | (4,842)
Exploration | 0 | 0 | (3,777)
Depreciation and amortization | 0 | 0 | (5,049)
Mining royalties | 0 | 0 | (11)
Total operating costs | 0 | 0 | (13,679)
Gross loss | 0 | 0 | (12,530)
Operating income (expenses), net |  |  |
Changes in provision for closure of mining units, note 15(b) | (6,013) | (12,701) | (3,365)
Derecognition of long-lived assets | (2,837) | 0 | 0
Net loss in sale of mining units | 0 | (18,550) | (3,014)
Administrative expenses | 0 | (941) | (111)
Reversal (provision) for contingencies | 0 | (423) | 901
Gain (loss) for sale in other assets | 0 | (162) | 3,200
Reversal of provision for closure of mining units for sale of mining units, note 15(b) | 0 | 11,700 | 0
Reversal of provision for impairment of inventories, note 8(c) | 0 | 1,345 | 706
Impairment loss of long-lived assets | 0 | 0 | (2,043)
Others, net | (1,147) | (6,871) | (1,793)
Total operating expenses, net | (7,160) | (9,406) | (5,519)
Operating loss | (7,160) | (9,406) | (18,049)
Other income (expense), net |  |  |
Finance costs, note 15(b) | (54) | (694) | (970)
Net gain (loss) from currency exchange difference | 11 | 2 | (50)
Total other expenses, net | (43) | (692) | (1,020)
Income tax | 0 | 0 | (4)
Loss from discontinued operations | $ (7,203) | $ (10,098) | $ (19,073)
Loss from the discontinued operations, per basic and diluted share, express in U. S. dollars | $ (30) | $ (40) | $ (70)

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