The commissioner may execute leases for the extraction of salt from the saline lands and lakes belonging to the state. Such leases shall provide for a royalty on all salt extracted therefrom of not less than ten percent of the actual sale price at the place of extraction. Said royalties shall be paid quarterly and accurate record shall be kept of all sales made. All leases made hereunder shall contain such conditions and shall provide for the cancellation of the lease by the commissioners for the breach thereof.