Chen Collection, Lower Volume Radical: Weapon (shū) Page 588, Entry 09 Guangyun and Jiyun: Pronounced yi (level tone). Identical to the character for medical doctor. The Book of the Great Mystery (Taixuanjing) by Yangzi uses this character, as well as the characters for shaman and prayer. It is also identical to the character for black gemstone (yi). The Supplement to the Dictionary of Rhymes (Yunhuibu) states that pine resin becomes poria after a thousand years, amber after another thousand years, and a black gemstone (yi) after another thousand years. It is also identical to the character for shade or screen (yi), which is the name of a type of tree. Ancient and Modern Notes (Gujinzhu) by Cui Bao states that the character for shade or screen (yi) is sometimes written as this character. The shade tree (yi) originates from Jiaozhou and is also called ebony.