Qing Yan (Green Salt) (Isometric cubic crystals, light yellow, luster)
【Naming】
【Source】
Newly Revised Materia Medica – Green Salt
【Common Usage Level】
D
【Origin】
A type of crystalline rock salt, a mineral containing sodium chloride.
【Characteristics】
Common Qing Yan (Green Salt) appears as isometric cubic crystals, or octahedrons and rhombs, etc. Sometimes it crystallizes into distorted crystals, sometimes into concave surfaces, and sometimes into granular dense massive or columnar shapes. It is brittle with a hardness of 2.5; specific gravity of 2.1~2.6, luster is glassy and translucent. Pure salt is white or colorless. Impure salt is often yellow, light yellow, or light blue. Streak is white. Salty taste.
【Identification】
Universal Relief Prescriptions: “White salt is the best.” Compendium of Materia Medica: “[Shizhen says] Herbalists say that Persian green salt is green in color, and that which is dry and not damp in rainy weather is genuine.” Seeking Truth in Materia Medica: “That which is angular, bright, and green in color is good.”
That which is green in color, massive in shape, large in size, and bright is the best.
【Category】
Minerals