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.
476,
477], 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.
461 et seq.].