25 U.S.C. § 2108

Nothing in this chapter shall impair any right of an Indian tribe organized under section 16 or 17 of the Act of June 18, 1934 (48 Stat. 987), as amended [25 U.S.C. 5123, 5124], to develop their mineral resources as may be provided in any constitution or charter adopted by such tribe pursuant to that Act [25 U.S.C. 5101 et seq.].