From Shennong's Herbal Classic. "Tang Ben Medicine": "The iron pendant is the red boiling of iron burned by the forging furnace, which is forged on the anvil and the leather armor falls. The books A and B are full of words. When a doctor treats a disease, he does not take medicine or eat powder, but cooks it with paste. If the pulp is iron drops, it will be the juice of steel. What falls is iron liquid, which is darker than iron. Tao said that soap can be dyed and clouds are iron slurry, which is wrong. "
It's from "Heavenly Crafting and Hammer". The place where wrought iron is baked is called coarse iron. When forging, the third consumption is iron flower and iron rod (1). (1) Tiehua and Tieluo: iron filings produced when forging iron.