Wu Collection, Lower Volume Radical: Stone (shí) Kangxi Strokes: 20 Page 838, Entry 25 Pronounced fan. Alum stone. Classic of Mountains and Seas (Shanhaijing): On Mount Nuchuang, the northern slope contains much ni stone. Guo commentary: This is alum stone. The people of Chu call it ni stone, and the people of Qin call it yu ni. Collected Rhymes (Yunhui): Another name is yu ze; it exists in five colors: blue, white, yellow, black, and deep red. Also, mountain alum, the name of a flower. Corrected Dictionary (Zhengzitong): Commonly called ding flower, the tree grows several feet tall with dense leaves and thick branches; it does not wither in winter, and its flowers are white and fragrant. Also called chang flower. Huang Tingjian says: In the wild areas of Jiangnan, local people gather the leaves of the ding flower and burn them to make ash, using it to dye purple into a dark black color without needing to use alum. Because of this, its name was changed to mountain alum. Collected Rhymes (Yunhui) erroneously calls it zheng flower and claims it is the Tang dynasty jade stamen flower, which is incorrect.