Xu Collection, Upper Volume. Radical: Metal (jīn). Iron. Kangxi strokes: 21. Page 1323, Entry 37. Ancient form: tie. Pronounced tie. In the Explanation of Graphs (Shuowen), it is defined as black metal. In the Book of Documents (Shujing), Tributary Regions of Yu (Yugong), it mentions: Their tribute consists of precious stones, iron, silver, and arrowheads. In the Records of the Grand Historian (Shiji), Biography of Economic Merchants, it states: Guo Zong of Handan built an industry through iron smelting; the ancestors of the Zhuo family of Shu were people of Zhao who became wealthy through iron smelting, as did the Bing family of Lu. In the Preface to the Eulogy on the Bronze Sword by Jiang Yan, it notes: In ancient times, bronze was used to make weapons, but by the Qin dynasty, conflict and warfare were rampant, and bronze was no longer sufficient, so iron was used as a substitute. Also, yellow iron refers to copper. In the Book of Documents (Shujing), Code of Lu, the commentary on the penalty of one hundred huan states: Huan is yellow iron. The sub-commentary explains: In ancient times, gold, silver, copper, and iron were all collectively referred to as metal. Here, the commentary says yellow iron, and the commentary on the Canon of Shun says yellow gold, both referring to what we now call copper. When ancient people paid to redeem punishments, they all used copper; the fact that some texts call it gold and others iron simply means that copper was classified as both metal and iron. Also, in the Book of Rites (Liji), Monthly Ordinances (Yueling), it mentions driving iron-colored black horses. The note says: Iron-colored horses have a color like iron. In the Book of Odes (Shijing), Odes of Qin (Qinfeng), it mentions: A team of four iron-colored horses, very stout. The commentary says: These are iron-colored black horses. The sub-commentary explains: Iron refers to the fact that its color is black like iron. Note that in modern collected commentaries, it is written as tie. Also a place name. In the Spring and Autumn Annals (Chunqiu), second year of Duke Ai, there is a battle at Tie. The note says: Tie is a place name in the State of Wei, located south of Qicheng. Also a water name. In the Classic of Mountains and Seas (Shanhaijing), the Bietie River originates from here. Also a beast name. In the Classic of Marvels (Shenyijing), there is a beast in the south called the iron-gnawer; it is the size of a water buffalo, the color of lacquer, eats iron and drinks water, and its dung can be used to make weapons as sharp as steel. Also a book title. In the Book of Han (Hanshu), Treatise on Literature and Arts, it mentions the Salt and Iron Discourse (Yantielun) in sixty chapters. Also a surname. According to the Zhengzitong, there was Tie Nanzhong during the Song dynasty and Tie Xuan during the Ming dynasty. Also, a compound surname. Helian Bobo changed his collateral relatives to the Tiefa clan, saying he wished his clan to be as strong and sharp as iron, capable of attacking and defeating enemies. Also, according to the Jiyun, pronounced die, referring to sharp iron.