Guksae or oksae (국새,옥새) is an official seal made for used in lieu of signatures in personal documents, office paperwork, contracts, art, or any item requiring acknowledgment or authorship in Republic of Korea. Guksae is carved with the characters called injang. With declaration of establishment of Republic of Korea in 1948, its government created a new State Seal, guksae (국새, 國璽) and it is used in promulgation of constitution, designation of cabinet members and ambassadors, conference of national orders and important diplomatic documents.
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Guksae Wikipedia(Text) CC BY-SA