The commissioner of public lands or his authorized representative shall have the right to enter any leased lands for the purpose of measuring the cubical contents of every opening from which coal has been extracted and to otherwise inspect the leased lands to ensure that proper royalties have been paid. The commissioner or his representative shall have the right to inspect all records, books or accounts pertaining to the mining, extraction, transportation and returns of coal produced from the leased lands and, at the request of the commissioner, the lessee shall furnish reports, samples, logs, assays or cores within reasonable bounds as the commissioner may determine to be necessary to the proper administration of the lands under lease. The value of any unpaid royalty shall become a prior lien upon the production from the leased lands and the improvements situated thereon.