This early Korean postage stamp belongs to the notable “Yin-Yang” issue of 1884, the first set designed for use by the Korean postal service under King Gojong’s modernization reforms. Though never officially issued for postal use due to the swift collapse of the nascent postal system following the Gapsin Coup in December 1884, these stamps remain vital to Korean philately. Printed using typography, this orange 25 mun denomination features the symbolic Yin-Yang emblem, a reflection of traditional Korean cosmology and national identity. The stamp has variable perforation and was never gummed, as was typical for early Korean productions. It is listed as Michel KR-IM I and Yvert 3, but remains unlisted in the Scott catalogue, underscoring its rarity and limited distribution. As part of a non-issued series, its historical and cultural significance is immense, representing a brief but symbolic moment in Korea’s postal and political history. Estimate "$50– 80".