Section 78A Power to vary rights by agreement.

Notwithstanding anything contained in this Act, a mine owner, a royalty owner, and the company or any two of them may, by agreement alter, extend, or otherwise vary their respective rights under the provisions of this Act with regard to any minerals to which this Act applies, but not so as to prejudice the rights of any mine owner, royalty owner, or company not a party to the agreement without his or their consent.