Zi Collection, Page Position: Upper, Radical: Cliff (hǎn), Page 123, Entry 05 Pronounced xi (falling tone) — Guangyun (Guangyun) Pronounced xi (falling tone) — Jiyun (Jiyun) Pronounced su (falling tone) A black whetstone. "The Jing Mountains produce du stone." — Classic of Mountains and Seas (Shanhaijing) Pronounced xiao (falling tone) — Jiyun (Jiyun) Meaning the same.