(a) Under regulations adopted by the commissioner, the commissioner may grant a prospecting permit to a qualified applicant. The permit gives the applicant the exclusive right to prospect for chlorides, sulphates, carbonates, borates, silicates, or nitrates of potassium, in land belonging to the state, for a period not exceeding two years. The area included in a permit may not exceed 2,560 acres of land in reasonably compact form. Upon showing to the satisfaction of the commissioner that valuable deposits of potassium compounds have been discovered by the permittee within the area covered by the permit, and that the land is chiefly valuable for these deposits, the permittee is entitled to a lease for all or a part of the land embraced in the prospecting permit, at a royalty of not less than two percent of the quantity or gross value of the output of potassium compounds and other related products, except sodium, at the point of shipment to market. The commissioner may lease land known to contain valuable deposits of potassium compounds that is not covered by permits or leases through advertisement, competitive bidding, or other methods prescribed by regulation. The area covered by the lease may not exceed 2,560 acres.

(b) Each lease shall be conditioned upon payment by the lessee of a royalty of not less than two percent of the quantity or gross value of the output of potassium compounds and other related products, except sodium, at the point of shipment to market, and the payment in advance of a rental of 25 cents an acre for the first calendar year or fraction of it, 50 cents an acre for the second calendar year, third calendar year, fourth calendar year, and fifth calendar year, and $1 an acre a year thereafter during the continuance of the lease. The rental for any one year shall be credited against royalties accruing for that year.

(c) Each lease shall be for a term of 20 years and so long thereafter as the lessee complies with the terms and conditions of the lease.