A cultural asset from Korea’s Joseon dynasty, stolen some 20 years ago and later held by a now-deceased Japanese collector, has been returned to South Korea, a foundation affiliated with the South Korean government said Tuesday.

The epitaph on porcelain of a high-ranking official of the dynasty who lived in the 14th and 15th centuries was donated last month to the National Museum of Korea in Seoul by the collector’s family, the Overseas Korean Cultural Heritage Foundation said.

The epitaph lists the achievements of the official, who was involved in the compilation of King Taejong’s records, part of the Annals of the Joseon Dynasty, which is listed in UNESCO’s Memory of the World Register.

The item was taken to Japan in 1998 after being stolen from the South Korean city of Gwangju. It later came into possession of collector Takashi Todoroki, who did not know it was stolen.

After the foundation learned that the antiquity was kept in Japan, it contacted Todoroki. He died last November, but his family donated the piece to the South Korean side, respecting his will.

The artifact may be designated as an important national cultural asset by the South Korean government, as it is well preserved and believed to have high historical value, sources close to the foundation said.