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Note 3 - Inventory
3 Months Ended
Mar. 31, 2021
Notes to Financial Statements  
Inventory Disclosure [Text Block]

(3)

INVENTORY

 

Inventory is valued at lower of average cost or net realizable value (NRV).  As of March 31, 2021, and December 31, 2020, coal inventory includes NRV adjustments of $1.1 million and $1.6 million, respectively.