MEXICO, Estados Unidos Mexicanos. 1905-pres. AR Medal (37mm, 23.52 g, 12h). Semicentennial of the Mexican Navy. Ciudad de México (Mexico City) mint. Dually dated 1917 and 1967. Merchant ship right; above, 1917 and 1967; below, CINCUENTENARIO/ DE LA MARINA/ NACIONAL / POR LA PATRIA, warship sailing left; POR EL MAR below. Grove 959a. Iridescent toning, hairlines. EF.