This 1916 Japanese commemorative stamp, denominated 3 sen and tied to cover sent from colonial Korea to Japan, was issued to celebrate the designation of Prince Hirohito as Crown Prince. The stamp features a stylized mandarin duck in a floral design, printed in yellow and red by typography, with a comb perforation of 12½ and no watermark. Listed as Scott JP 153, Michel JP 128, Yvert 150, Stanley Gibbons JP 190, and Sakura C16, this issue is part of a series that highlights significant imperial milestones and nature motifs. The postmark is the official commemorative cancel for the Rei Taishi (Crown Prince) event, dated 10 December in the fifth year of Taishō (1916). Only 5,762,000 copies of this stamp were issued, making it one of the scarcer early Japanese commemoratives. The envelope shows manuscript calligraphy on native paper, some edge wear and loss at top corners, but remains a historically meaningful postal artifact from the Japanese occupation of Korea. Estimate "$100 – 130"