The verdict from the National Palace Museum of Korea and the Cultural Heritage Administration, which examined and tested the artifact for three months before making its announcement.
The Korea Times said Tuesday the turtle-shaped seal will likely be declared a national treasure by South Korea.
The seal was one of three normally used by Joseon kings to sign off on various official correspondence during the kingdom, which ruled the peninsula from 1392 until 1910. King Gojong used the seal toward the end of the dynasty and applies it to letters sent to various European kings at the dawn of the 20th century.
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