楽浪郡
The "shinjū-kyō" style of bronze mirror originated in China and was frequently produced during the Han dynasty, Three Kingdoms, and Six Dynasties (1st–6th centuries CE). With the spread of Chinese bronze casting technology, "shinjūkyō" were also produced in Japan and the Lelang Commandery and Daifang Commandery in the Korean peninsula. The c. 297 "Wei zhi" (魏志 "Records of Wei"), which is part of the "Records of the Three Kingdoms" (三國志), has the first historical reference to bronze mirrors in Japan. It chronicles tributary relations between Queen Himiko of Wa and the Wei court, and records that in 239, Emperor Cao Rui sent presents to Himiko, including "one hundred bronze mirrors" (tr. Tsunoda 1951:15).