Wu Collection, Lower Volume Radical: Stone (shí) 磋 Kangxi stroke count: 15 Page 834, Entry 27 According to Broad Rimes (Guangyun), pronounced cuo (level tone). According to Collected Rimes (Jiyun), Rime Collection (Yunhui), and Standard Rimes (Zhengyun), pronounced cuo (level tone). To polish or grind. As stated in the Book of Odes (Shijing), Weifeng section: Like cutting and like polishing. The commentary states: The working of ivory is called cuo. It is commonly written as a variant form (cuo). Additionally, according to Five Sounds Rime Collection (Wuyin Jiyun), pronounced cuo (falling tone). The meaning is the same.