ITG FAQ #10 Answer-Are mineral interests treated differently than surface rights?
Many valuable mineral interests have been identified on Indian lands. The Department of the Interior has interpreted the term "minerals" to include all substances, except oil and gas, with value apart from the surface estate from which income may be realized. Mineral leases on Indian lands were first authorized in 1891 for terms of ten years. Congress delegated authority to promulgate rules and regulations governing mineral leases on Indian lands to the Secretary of the Interior.