The source is from smithsonite of carbonate of calcite group, mainly containing zinc carbonate. The medicine is mainly produced in Guangxi, Hunan, and Sichuan. Impurity is removed from the material after being collected. It is calcined, or quenched with vinegar or with Sanhuang Tang (Decoction), containing Huanglian (Rhizoma Coptidis ), Huangbai (Cortex Phellodendri) and Dahuang (Radix et Rhizoma Rhei) and then dried in the sun and ground into fine powder with water for use.

Medicinal Properties: Sweet in flavor, mild in nature, and attributive to the liver and stomach meridians.

Actions: Remove nebula to improve eyesight, eliminate dampness and promote tissue regeneration.

Application
1.It can be used to treat eye diseases. For conjunctivitis, equal amount of the Chinese medicinal herbs such as Fenghuaxiao (Natrii Sulfas, weathering) and Mangxiao (Natrii Sulfas) can be elutriated and used as eye drops. For nebula, it is used in combination with Mangxiao (Natrii Sulfas) to wash the local area, and also with Haipiaoxiao (Ossa sepiae seu Sepiae) and Pengsha (Borax) as eye drops.
2. For ulceration that does not heal and purulent skin lesion, together with Hai' ercha (Catechu) it is ground into powder after mixed with sesame oil and applied to the local area. For yin ulcer and damp itching due to yin perspiration, it is alone ground into powder and applied to the local area.

Usage and Dosage: Proper amount is used for external application. It can be elutriated and used as an eye drops. The powder can be applied externally or mixed with water for application.