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REVENUE AND COST OF SALES (Tables)
 12 Months Ended
Dec. 31, 2017
Revenue And Cost Of Sales  
Schedule of Cost of Sales

    2017     2016     2015  
Production costs   $ 19,417,844     $ 17,263,182     $ 7,538,147  
Depreciation and depletion     2,557,286       1,897,618       1,035,053  
    $ 21,975,130     $ 19,160,800     $ 8,573,200