25 U.S.C. § 2203: Adoption of land consolidation plan with approval of Secretary

except as provided by subsection (c), the sale price or exchange value received by the tribe for land or interests in land covered by this section shall be no less than within 10 per centum of the fair market value as determined by the Secretary; if the tribal land involved in an exchange is of greater or lesser value than the land for which it is being exchanged, the tribe may accept or give cash in such exchange in order to equalize the values of the property exchanged; any proceeds from the sale of land or interests in land or proceeds received by the tribe to equalize an exchange made pursuant to this section shall be used exclusively for the purchase of other land or interests in land; the Secretary shall maintain a separate trust account for each tribe selling or exchanging land pursuant to this section consisting of the proceeds of the land sales and exchanges and shall release such funds only for the purpose of buying lands under this section; and any tribe may retain the mineral rights to such sold or exchanged lands and the Secretary shall assist such tribe in determining the value of such mineral rights and shall take such value into consideration in determining the fair market value of such lands. The Secretary must execute such instrument of conveyance needed to effectuate a sale or exchange of tribal lands made pursuant to an approved tribal land consolidation plan unless he makes a specific finding that such sale or exchange is not in the best interest of the tribe or is not in compliance with the tribal land consolidation plan. The Secretary may execute instruments of conveyance for less than fair market value to effectuate the transfer of lands used as homesites held, on December 17, 1991 , by the United States in trust for the Cherokee Nation of Oklahoma. Only the lands used as homesites, and described in the land consolidation plan of the Cherokee Nation of Oklahoma approved by the Secretary on February 6, 1987 , shall be subject to this subsection.