Wu Collection, Upper Volume Radical: Jade (yù) Character: yi Kangxi Stroke Count: 16 Page 740, Entry 19 Collected Rhymes (Jiyun): Pronounced yi. A beautiful stone, black in color. Orthodox Rhymes (Zhengyun): Black jade. The old annotation describing it as a beautiful black stone is incorrect. Materia Medica (Bencao): Amber that is one thousand years old is called yi. It resembles jade, is as black as pure lacquer, and can be as large as a carriage wheel. Yongchang has a black jade mirror, which is exactly this yi. Textual Research: The Collected Rhymes (Jiyun) indicates it is pronounced xi. However, after careful examination, the character xi belongs to the xia initial, while the character yan belongs to the ying initial. The combination of these two cannot produce the sound xi. Based on the Collected Rhymes, the pronunciation has been corrected to yi.