(1) If the amount of the royalty paid by the holder of a mining tenement under section 18 in a royalty year is greater than the correct amount of royalty payable by the holder in respect of the royalty year, the holder is entitled to a refund equal to the difference.
(2) If the amount of royalty paid or payable by the holder of a mining tenement under section 18 in a royalty year is less than the correct amount of royalty payable by the holder in respect of the royalty year, the holder must pay as royalty an amount equal to the difference.