The Mojing 墨经 "Book of inkstones" is a small book on the production and use of inkstones written by the Song period 宋 (960-1279) scholar Chao Guanzhi 晁贯之, courtesy name Chao Jiyi 晁季一. It is only known that he once occupied a position as examining editor (jiantaoguan 检讨官), and that he was a relative to the Song period bibliographer Chao Gongwu 晁公武 (author of the Junzhai dushu zhi 郡斋读书志). He dedicated his whole life to the study of inkstones. His book Mojing deals with 20 topics, from the right kind of pine tree to the production of the stones.
The Mojing is included in a lot of collectanea, like Shuofu 说郛, Jindai mishu 津逮秘书, Tang-Song congshu 唐宋丛书, Chaoshi congshu 晁氏丛书, Xuejin taoyuan 学津讨原, Xu baichuan xuehai 续百川学海, Yimen guangdu 夷门广牍, Yipu souqi 艺圃搜奇,Siku quanshu 四库全书 and Meishu congshu 美术丛书.