The county treasurer in each of the organized counties of the state of Washington, shall be by his or her county provided with a seal of office for the authentication of all tax deeds, papers, writing and documents required by law to be certified or authenticated by him or her. Such seal shall bear the device of crosskeys and the words: Official Seal Treasurer . . . . . . County, Washington; and an imprint of such seal, together with the certificate of the county treasurer that such seal has been regularly adopted, shall be filed in the office of the county auditor of such county.