The Gold Seal of the "Kan no Wa no Na no Kokuo (king of the Na state of the Wa [vassal] of Han Dynasty)" was unearthed in Kananosaki on Shikanoshima at the mouth of Hakata Bay (in today's Higashi-ku, Fukuoka City) in Tenmei 4 of the Edo period (1784). It was found under a stone that was so heavy it required two adults to lift it. The discoverer was a farmer called Jinbei. (There is also a theory that the seal was actually found by Hideji and Kihei who may have been employees of Jinbei.) Jinbei submitted his "Report on the Unearthing of a Gold Seal by Jinbei, a Farmer of the Shikanoshima Village in Tenmei 4" to Genjiro Tsuda, the bugyo (district commissioner) of the Naka-gun district office. This is the document that offers us the information on how the Gold Seal was found.
　 The first person who appraised the Gold Seal from Shikanoshima was Nanmei Kamei, the director of the Kantokan, the Western Learning Center of the Kuroda-han (clan). In his "Kinin Ben", an appraisal report on the Gold Seal, he illustrated the importance of the seal by claiming that it was the very seal mentioned in the chapter "Records of Eastern Barbarians" of "Hou Han Shu (History of the later Han Dynasty)". The Chinese chronicle says, "The Na state of the Eastern tribe, Wa (Japan) sent a messenger with a tribute to the emperor in 57 AD. The messenger introduced himself as a high official. The state lies in the south of Wa. The emperor Guanwu conferred a seal with a tassel". Thanks to Nanmei's efforts, the Gold Seal was preserved in the warehouse of the Kuroda clan of Chikuzen Province for a long time. The Kuroda family donated the seal to the city of Fukuoka in 1978.