味咸，微温，无毒。主崩中漏下，破子脏中血，症瘕结气，寒热腹痛，无子，阴痿
补不足，疗男子茎头寒，阴下湿痒，去臭汗，消水肿。《药性论》云∶味甘，平。主补肾气
精乏，腰疼膝冷，湿痹，能暖女子子宫久冷，冷症寒瘕，止月水不定。
萧炳云∶
臣。日华子云∶治带下，温疫，冷气，补五劳七伤。桑螵蛸为使。恶∶泽泻、菌桂、石
葵、雷丸、蛇蜕皮。畏∶菟丝。忌∶羊血。
味咸辛，平，有小毒。主久痢，五痔，金疮，面上瘢酐，面膏药用之。日华子云∶
平，无毒。镇心，补五脏，治惊痫、嗽呕及吐痰。《圣惠方》∶治酐黯斑点。细研，人乳汁调
涂面，每夜用之。《谭氏小儿方》∶疗豆疮瘢，面 。细研，水调，夜涂之明旦洗去，平复。
《外台秘要》∶治渣鼻 。
微寒。主疗下部及脱肛。日华子云∶生铁 后飞淘去粗，赤汁烘干用。治癣及恶疮疥，
蜘蛛咬，蒜磨生油敷并得。《肘后方》∶治熊虎所伤毒痛。煮生铁，令有味，以洗之。《千金
方》∶治耳聋。烧赤投酒中饮之，仍以磁石塞耳中，夜去之，旦别着。
味咸，平，无毒。主安心神，坚骨髓，除百病，变白，润肌肤，令人不老，体健能食
久服令人身重肥黑。合和诸药，各有所主。其造作粉飞炼有法，文多不载，人多取杂铁作
飞之，其体重，真钢则不尔。其针砂，市人错柔铁为屑，和砂飞为粉卖之，飞炼家亦莫辨
取钢铁为粉胜之。
[Yangqi Shi (Styrox)]
Salty in flavor, slightly warm in nature, non-toxic. Primarily treats metrorrhagia and leukorrhea (abnormal uterine bleeding or discharge), breaks up blood stasis in the uterus, addresses zheng jia qi jie (abdominal masses and qi stagnation), cold-heat abdominal pain, infertility, and impotence. It tonifies deficiencies, treats coldness at the glans penis in men, dampness and itching in the genital area, removes foul sweat, and reduces edema. *Yao Xing Lun* states: Sweet in flavor, neutral in nature. Primarily tonifies kidney qi, treats seminal deficiency, lower back pain with cold knees, damp-bi syndrome, warms the female uterus affected by chronic cold, treats cold-pattern han jia (cold-induced abdominal masses), and regulates irregular menstruation. Xiao Bing states: It serves as a minister herb. Ri Hua Zi states: Treats leukorrhea, epidemic febrile diseases, cold qi, and tonifies the five excesses and seven injuries. Sangpiaoxiao is used as an guiding herb. Aversions: Ze xie, Jun gui, Shi kui, Lei wan, She tuipi. Taboos: Sheep blood.
[Tie Fen (Iron Powder)]
Salty and acrid in flavor, neutral in nature, slightly toxic. Primarily treats chronic dysentery, five types of hemorrhoids, metallic trauma, facial keloids, and is used in facial cosmetic pastes. Ri Hua Zi states: Neutral in nature, non-toxic. Calms the heart and spirit, tonifies the five zang organs, treats fright epilepsy, cough, vomiting, and expectoration. *Shenghui Fang* states: Treats facial dullness and spots. Grind finely, mix with human milk, apply to the face, use every night. *Tan Shi Xiao Er Fang* states: Treats post-varicella scars. Grind finely, mix with water, apply at night, wash off at dawn, restoring smooth skin. *Waitai Mi Yao* states: Treats rhinophyma.
[Sheng Tie Luo (Fallen Iron)]
Slightly cold in nature. Primarily treats lower body disorders and rectal prolapse. Ri Hua Zi states: Take fallen iron filings, fly-wash repeatedly to remove coarse particles, dry over red juice until dry. Treats tinea and malignant sores/scratches, spider bites; applying garlic paste mixed with raw oil is also effective. *Zhouhou Fang* states: Treats toxic pain from bear or tiger bites. Boil fallen iron until it has a distinct taste, use to wash the wound. *Qianjin Fang* states: Treats deafness. Red-hot iron is thrown into wine for drinking, while magnetite is inserted into the ears at night and removed in the morning, then replaced.
[Zhen Sha (Needle Sand/Iron Filings)]
Salty in flavor, neutral in nature, non-toxic. Primarily calms the mind and spirit, strengthens bone marrow, eliminates hundred diseases, whitens the complexion, moistens the skin, prevents aging, makes the body robust and appetite good. Long-term use leads to heavy body, obesity, darkening of skin, and hair. When combined with other herbs, each has its specific indication. The method of manufacturing powder via flying and refining follows strict rules; due to length, details are omitted. People often use scrap iron to make flying powder, which is heavy; true steel does not behave this way. What is sold as Zhen sha in markets is soft iron filed into dust, mixed with sand, and refined into powder for sale; even expert refiners cannot distinguish it. It is recommended to use powder made from steel instead.