1. The leasing of any of the lands referred to in this article in such manner as the legislature may prescribe, for grazing, agricultural, commercial and homesite purposes, for a term of ten years or less, without advertisement;
2. The leasing of any of said lands, in such manner as the legislature may prescribe, whether or not also leased for grazing and agricultural purposes, for mineral purposes, other than for the exploration, development, and production of oil, gas and other hydrocarbon substances, for a term of twenty years or less, without advertisement, or,
3. The leasing of any of said lands, whether or not also leased for other purposes, for the exploration, development, and production of oil, gas and other hydrocarbon substances on, in or under said lands for an initial term of twenty (20) years or less and as long thereafter as oil, gas or other hydrocarbon substance may be procured therefrom in paying quantities, the leases to be made in any manner, with or without advertisement, bidding, or appraisement, and under such terms and provisions, as the legislature may prescribe, the terms and provisions to include a reservation of a royalty to the state of not less than twelve and one-half per cent of production.