(a) Applications or requests by the Indian owners of restricted or trust land, or by others, that such land be leased or offered for lease for lead and zinc mining purposes should be addressed to the Secretary of the Interior and submitted through the superintendent of the Quapaw Indian Agency. Upon receipt of such applications or requests, the superintendent shall give consideration thereto and forward the same to the Commissioner of Indian Affairs with his report and recommendation.

(b) In no instance will a new lease be executed and delivered (or advertised for sale to the highest bidder) unless the Indian owner thereof, if an adult who has not been specifically found by the Secretary of the Interior to be personally incompetent to transact ordinary business affairs, has agreed to the terms of said lease or the terms under which said lease is advertised for lease, except in cases where the land is owned by several co-tenants, and, in such cases, no such lease shall be given or advertised for sale unless the co-owners or a majority in interest, if adults, and not specifically declared incompetent, have first consented thereto: Provided, That in the event the majority in interest is owned by minors, or adults specifically found to be incompetent, then and in that event, the Secretary of the Interior reserves the right to lease the entire tract if, in his opinion, such leasing will inure to the best interest of the restricted Indian owners.