Quanzhi 泉志 "On the source (of wealth)" is a book on money written during the Southern Song period 南宋 (1127-1279) by Hong Zun 洪遵 (1120－1174), courtesy name Jingyan 景嚴, from Poyang 鄱陽 in the prefecture of Raozhou 饒州 (today in Jiangxi province). It is the earliest surviving complete treatise on money. The term quan 泉 "source" is pronounced very similarly to the word qian 錢 "money", and was used with the meaning of the latter, for instance, in the designation of the capital mint (baoquanju 寳泉局 "Office for the source of wealth"), but was also used in the literal meaning, as can be seen in the name of the secondary capital mint, the baoyuanju 寳原局 "Office for the origin of wealth". The book with a length of 15 juan was therefore also called Qianzhi 錢志.
It was finished in 1149 but was never printed. It has only survived as a manuscript in the Ming-period 明 (1368-1644) encyclopaedia Yongle dadian 永樂大典, based on which Weng Shupei 翁樹培 (1765-1811) reconstructed the original text. The book includes excellent reproductions of 265 types of coins from oldest times until the end of the Five Dynasties period 五代 (907-960). The coins are classified into nine types, namely standard money (zhengyongpin 正用品), forgeries (weipin 偽品), non-dateable items (bu zhi niandai pin 不知年代品), "celestial" monies (tianpin 天品), knive- and spade-shaped coins (dao bu pin 刀布品), foreign coins (waiguo pin 外國品), strange coins (qipin 奇品), "divine money" (shenpin 神品) and talismanic coins (yasheng pin 厭勝品).
The text describes how these coins were cast, their appearance and inscriptions. The Quanzhi is very important for the most precious coins of earlier centuries, like tianxin 天信, xuzhu 續銖, jinghe 景和, "large" coins (daqian 大錢, i.e. coins of higher denominations) with the inscription qianfeng quanbao 乾封泉寶, or moneys called tiance 天策, tiande 天德, tianzan 天贊, tiangan 天感, guangzheng 廣政 or yongtong quanhua 永通泉貨, or the money of the Western Xia empire 西夏 (1038-1227).
The descriptions of Hong Zun's Quanzhi are wholly identical with the characteristics of surviving specimen which underlines the high scholarly quality of his book. Hong Zun made use of a large amount of sources (nearly a hundred) for his book , from official dynastic histories to "brush-note"-style (biji 筆記) essay collections and early, now lost, treatises on money, for instance, Feng Yan's 封演 (mid-8th cent.) Qianpu 錢譜 from the Tang period 唐 (618-907), Zhang Tai's 張臺 Qianpu 錢譜 from the 10th century or Tao Yue's 陶岳 (d. 1022) Huoquanlu 貨泉錄 "On commodities and money" from the early Song period. Of particular interest are the illustrations of 83 foreign coins from Japan or Persia that came to China by trade.
Hong Zun's scholarly methods are of a high quality. He is, for example, very critical to an oversimplification of the system of coins and the methods of coin productions during the Spring and Autumn 春秋 (770-5th cent. BCE) and Warring States 戰國 (5th cent.-221 BCE) periods.