Maifanshi (stone named after Maifantuan) is produced in Shandong, Inner Mongolia, Fuxin, Liaoning and other places. The reserves vary from place to place, and the quality varies greatly. The medical stone recorded in Compendium of Materia Medica was the earliest discovered and mined, among which the medical stone in Naiman Banner, Tongliao City, Inner Mongolia has the best quality. The only medical stone named "medical stone" has the following identification methods: look at the pattern of medical stone, white spots are black spots of wheat grains, yellow is a trace element, and the color of medical stone is cyan or crane yellow. The method to identify the true and false medical stone is 1. If the other party's color is not medical stone, method 2: you can identify the true and false medical stone by detecting PH value or trace elements. Method 3: you can taste it in a more earthy way. Soak the Chinese medical stone cup in water for 30 minutes, which is particularly soft and sweet. The mineral content inside is basically the same as that of Nongfu Spring!