Da Qing Yan

Da Qing Yan (大青盐) is the Chinese materia medica name for halite, a naturally occurring crystalline form of sodium chloride (NaCl), commonly known as rock salt. It is not a plant but a mineral substance, typically harvested from salt deposits or salt lakes in northern and northwestern China. The crystals are colorless, white, blue, or pale violet, and dissolve readily in water. In traditional Chinese medicine, Da Qing Yan is classified as cold and salty, entering the Kidney, Heart, and Stomach channels. It is used to cool blood, clear heat, brighten the eyes, soften hard masses, and detoxify. Classical indications include sore swollen gums, toothache, throat soreness, and red eyes, and it appears as an ingredient in ophthalmic and dental preparations.