At the main venue for the 2025 International Museum Day celebrations on Sunday in Changchun, Jilin province, Jin Mingnan and his wife, Gao Jindan, donated a gold seal to the Ji'an Museum.

The couple had recently acquired the seal at an auction in Hong Kong for HK$10.79 million ($1.38 million). It dates back to the Western Jin Dynasty (265-316) and is said to have been outside of China for the past 1,700 years.

The words "Jin Gaogouli (Goguryeo) Guiyihou" are inscribed on the seal. The inscription is neat and clear, with strokes transitioning naturally and smoothly. It refers to an official seal of the Goguryeo ethnic group issued by the dynasty government.

This golden seal is an indicator of enfeoffment, a status that can be viewed as a type of feudal contract offering land in exchange for loyalty. It suggests that the kingdom of Goguryeo was effectively under the jurisdiction of the Central Plains dynasty during the Western Jin era.

The button and body of the seal were cast as a whole, measuring 2.4 centimeters long and 2.3 cm wide on the seal face, with a height of 2.8 cm. It is the largest seal related to the tribute and enfeoffment of Goguryeo during the Western Jin Dynasty found so far.