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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Products, Properties and Production of Minerals (Details) | 12 Months Ended
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Dec. 31, 2019
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES |
Option to sell prior to the completion of refining (as a percent) | 90.00%
Minimum |
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES |
Period over which concentrates are provisionally priced at the end of a period after delivery to the customer | 30 days
Maximum |
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES |
Period over which concentrates are provisionally priced at the end of a period after delivery to the customer | 90 days

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- Definition Period over which concentrates are provisionally priced, whereby the selling price is subject to final adjustments at the end of a period after delivery to the customer. + References No definition available. + Details
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