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OPERATING SEGMENT REPORTING - Summary of Reportable Operating Segments (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2021 | Sep. 30, 2021 | Jun. 30, 2021 | Mar. 31, 2021 | Dec. 31, 2020 | Sep. 30, 2020 | Jun. 30, 2020 | Mar. 31, 2020 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Revenue from gold and silver sales |  |  |  |  |  |  |  |  | $ 136,541,000 | $ 104,789,000 | $ 117,019,000
Depreciation and depletion |  |  |  |  |  |  |  |  | (23,798,000) | (22,910,000) | (24,753,000)
Gross profit (loss) | $ (5,897,000) | $ 344,000 | $ 4,059,000 | $ (4,986,000) | $ (13,687,000) | $ (701,000) | $ (8,875,000) | $ (3,685,000) | (6,480,000) | (26,948,000) | 8,986,000
Advanced projects |  |  |  |  |  |  |  |  | (12,439,000) | (11,681,000) | (9,520,000)
Impairment loss on mineral property interests and plant and equipment (Note 8) |  |  |  |  |  |  |  |  | 0 | (83,805,000) |
Loss from investment in Minera Santa Cruz S.A. |  |  |  |  |  |  |  |  | (7,533,000) | (1,517,000) | (8,754,000)
Other operating |  |  |  |  |  |  |  |  |  | (1,968,000) |
Loss before income and mining taxes |  |  |  |  |  |  |  |  | (64,199,000) | (153,715,000) | (63,591,000)
Capital expenditures |  |  |  |  |  |  |  |  | 36,033,000 | 13,925,000 | 30,270,000
United States Reportable Segment [Member] |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Depreciation and depletion |  |  |  |  |  |  |  |  | (8,502,000) | (11,785,000) | (10,934,000)
Gross profit (loss) |  |  |  |  |  |  |  |  | (3,288,000) | (21,366,000) | (701,000)
Advanced projects |  |  |  |  |  |  |  |  | (440,000) | (1,071,000) | (649,000)
Impairment loss on mineral property interests and plant and equipment (Note 8) |  |  |  |  |  |  |  |  |  | (83,805,000) |
Other operating |  |  |  |  |  |  |  |  |  | (1,390,000) |
Segment loss |  |  |  |  |  |  |  |  | (9,603,000) | (114,409,000) | (9,904,000)
Capital expenditures |  |  |  |  |  |  |  |  | 2,416,000 | 4,821,000 | 18,806,000
Canada |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Depreciation and depletion |  |  |  |  |  |  |  |  | (15,296,000) | (10,883,000) | (13,271,000)
Gross profit (loss) |  |  |  |  |  |  |  |  | 2,447,000 | (4,070,000) | 5,666,000
Advanced projects |  |  |  |  |  |  |  |  | (2,635,000) | (6,088,000) | (1,636,000)
Other operating |  |  |  |  |  |  |  |  |  | (578,000) |
Segment loss |  |  |  |  |  |  |  |  | (15,205,000) | (17,186,000) | (21,749,000)
Capital expenditures |  |  |  |  |  |  |  |  | 33,617,000 | 9,104,000 | 11,464,000
Mexico Reportable Segment [Member] |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Depreciation and depletion |  |  |  |  |  |  |  |  |  | (242,000) | (548,000)
Gross profit (loss) |  |  |  |  |  |  |  |  | (5,640,000) | (1,512,000) | 4,021,000
Advanced projects |  |  |  |  |  |  |  |  | (4,345,000) | (4,522,000) | (7,235,000)
Segment loss |  |  |  |  |  |  |  |  | (9,999,000) | (6,547,000) | (3,214,000)
MSC |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Loss from investment in Minera Santa Cruz S.A. |  |  |  |  |  |  |  |  | (7,533,000) | (1,517,000) | (8,754,000)
Segment loss |  |  |  |  |  |  |  |  | (7,533,000) | (1,517,000) | (8,754,000)
Los Azules |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Advanced projects |  |  |  |  |  |  |  |  | (5,019,000) |  |
Segment loss |  |  |  |  |  |  |  |  | (6,717,000) | (2,121,000) | (3,411,000)
Total Segment |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Depreciation and depletion |  |  |  |  |  |  |  |  | (23,798,000) | (22,910,000) | (24,753,000)
Gross profit (loss) |  |  |  |  |  |  |  |  | (6,481,000) | (26,948,000) | 8,986,000
Advanced projects |  |  |  |  |  |  |  |  | (12,439,000) | (11,681,000) | (9,520,000)
Impairment loss on mineral property interests and plant and equipment (Note 8) |  |  |  |  |  |  |  |  |  | (83,805,000) |
Loss from investment in Minera Santa Cruz S.A. |  |  |  |  |  |  |  |  | (7,533,000) | (1,517,000) | (8,754,000)
Other operating |  |  |  |  |  |  |  |  |  | (1,968,000) |
Segment loss |  |  |  |  |  |  |  |  | (49,056,000) | (141,780,000) | (47,032,000)
General and Administrative and other |  |  |  |  |  |  |  |  | (15,143,000) | (11,935,000) | (16,559,000)
Gold and silver sales |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Revenue from gold and silver sales | $ 34,966,000 | $ 37,129,000 | $ 40,706,000 | $ 23,740,000 | $ 27,703,000 | $ 27,395,000 | $ 18,291,000 | $ 31,400,000 | 136,541,000 | 104,789,000 | 117,019,000
Gold and silver sales | United States Reportable Segment [Member] |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Revenue from gold and silver sales |  |  |  |  |  |  |  |  | 79,205,000 | 48,884,000 | 43,847,000
Gold and silver sales | Canada |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Revenue from gold and silver sales |  |  |  |  |  |  |  |  | 50,704,000 | 41,452,000 | 50,058,000
Gold and silver sales | Mexico Reportable Segment [Member] |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Revenue from gold and silver sales |  |  |  |  |  |  |  |  | 6,632,000 | 14,453,000 | 23,114,000
Gold and silver sales | Total Segment |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Revenue from gold and silver sales |  |  |  |  |  |  |  |  | 136,541,000 | 104,789,000 | 117,019,000
Product [Member] |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Production costs applicable to sales |  |  |  |  |  |  |  |  | (119,223,000) | (108,827,000) | (83,280,000)
Product [Member] | United States Reportable Segment [Member] |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Production costs applicable to sales |  |  |  |  |  |  |  |  | (73,991,000) | (58,465,000) | (33,614,000)
Product [Member] | Canada |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Production costs applicable to sales |  |  |  |  |  |  |  |  | (32,961,000) | (34,639,000) | (31,121,000)
Product [Member] | Mexico Reportable Segment [Member] |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Production costs applicable to sales |  |  |  |  |  |  |  |  | (12,272,000) | (15,723,000) | (18,545,000)
Product [Member] | Total Segment |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Production costs applicable to sales |  |  |  |  |  |  |  |  | (119,224,000) | (108,827,000) | (83,280,000)
Exploration | United States Reportable Segment [Member] |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Production costs applicable to sales |  |  |  |  |  |  |  |  | (5,875,000) | (6,777,000) | (8,554,000)
Exploration | Canada |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Production costs applicable to sales |  |  |  |  |  |  |  |  | (15,017,000) | (6,450,000) | (25,779,000)
Exploration | Mexico Reportable Segment [Member] |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Production costs applicable to sales |  |  |  |  |  |  |  |  | (14,000) | (513,000) |
Exploration | Los Azules |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Production costs applicable to sales |  |  |  |  |  |  |  |  | (1,698,000) | (2,121,000) | (3,411,000)
Exploration | Total Segment |  |  |  |  |  |  |  |  |  |  |
Operating Segment Reporting |  |  |  |  |  |  |  |  |  |  |
Production costs applicable to sales |  |  |  |  |  |  |  |  | $ (22,604,000) | $ (15,861,000) | $ (37,744,000)

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