Yanpu 硯譜 "Notes on inkstones" is a short text written by an unknown person during the Southern Song period 南宋 (1127-1279). In its earliest form in the series Baichuan xuehai 百川學海, not even a year of publication is mentioned.
The 32 paragraphs are a loose collection of miscellaneous statements about inkstones, their place of origin and how they were used by famous masters like Ouyang Xiu 歐陽修 (1007-1072), Su Shi 蘇軾 (1037-1101), Tang Xun 唐詢 (1005-1064) or Zheng Qiao 鄭樵 (1104-1162). Even in these few lines, a lot of errors are included, like the jade inkstones produced by Xu Hanyang 許漢陽, information on which is only derived from a story of Master Gushenzi's 谷神子 Boyiji 博異記, in which the stone belongs to the Dragon Maid 龍女, and not to Xu Hanyang. Yet there is also interesting information not found in other books.
The Yanpu is included in the series Baichuan xuehai, Shuofu 說郛 and Siku quanshu 四庫全書.