The medicine refers to the magnetic iron ore magnetite, mainly including Fe3O4. It is mainly produced in the areas of Hebei, Shandong, and Liaoning, etc. and mined at any time and stored in the dry place. It is broken into pieces or quenched with vinegar and ground into powder for medication.

Pungent and salty in flavor, cold in nature and attributive to the liver, heart and kidney meridians.

Tranquilize the mind, calm the liver and suppress the sthenic yang, improve auditory and visual acuity, improve inspiration by invigorating kidney-qi and relieve dyspnea. 

1. For deficiency of yin leading to hyperactivity of yang manifested as irritability, palpitation, insomnia, dizziness, headache and epilepsy, usually combined with Zhusha (Cinnabaris), Shijueming ( Concha Haliotidis ), Baishaoyao ( Radix Paeoniae Alba ), and Shengdihuang (Radix Rehmanniae ) , etc.

2. For insufficiency of the liver-yin and kidney-yin manifested as tinnitus, deafness, and blurring of vision, etc., it can be combined with Shudihuang (Radix Rehmanniae Praeparatae ), Shanzhuyu ( Fructus Corni ) and Wuweizi (Fructus Schisandrae), etc., such as Erlong Zuoci Wan (Pill) ; for insufficiency of the liver and kidney with blurring of vision, it can be combined with Gouqizi (Fructus Lycii ) and Nüizhenzi ( Fructus Ligustri Lucidi ).

3. For shortness of breath due to insufficiency of kidney-qi, it is usually combined with Daizheshi (Haematitum), Wuweizi (Fructus Schisandrae) and Hutaorou ( Caro Juglamdis).

10 - 30 g is used in decoction for oral use, which is broken into pieces and decocted early. 1 - 3 g is used in pill and powder form.  

It can not be used in large amount or prolonged time since it is not easily digested, and used with caution in cases with deficiency of the spleen and stomach.