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Salty in flavor, neutral in nature, non-toxic. Primarily nourishes Kidney Qi (Kidney Energy), strengthens Yin essence, treats ulcerative sores of the genitalia, stops intestinal diarrhea and dysentery, and treats mouth ulcers and sore throat. Long-term consumption benefits Yuan Qi (Primal Energy), prevents hunger, and prolongs life. Also known as Shi Nie (Stone Black Lead) or Shi Mo (Graphite). Originates from Yangcheng County, Yingchuan Commandery; can be harvested at any time.

The therapeutic effects of these five types of stone clays are similar to those recorded in *Shennong Bencao Jing* (Divine Farmer's Materia Medica), and their medicinal properties are also comparable. The entries in *Mingyi Bielu* (Record of Famous Physicians) are detailed here for completeness; currently, common usage involves only two types: Chishizhi (Red Stone Clay) and Baishizhi (White Stone Clay). *Xianjing* (Scriptures of Immortals) also utilizes Baishizhi to coat alchemical furnaces. High-quality Baishizhi originates from Wu Commandery and shares the same source as Chishizhi. Chishizhi is predominantly red with good luster; it is suitable only for astringing and stopping diarrhea but cannot be used in Wushi San (Five-Mineral Powder). High-quality Chishizhi also originates from Wuling, Jianping, and Yiyang. Currently, Wushi San exclusively uses the variety from Yiyang, sourced eighty li east of the county boundary. It resembles pig brain, has a lovely bright red color, regenerates immediately after harvesting, yet cannot stop dysentery, and thus is not adopted. Although the other three types of stone clays exist, there is no authentic supply; only Heishizhi (Black Stone Clay) can be used for painting.

[Verification] Yiyang is Shenzhou. The stone produced there is named Taohua Shi (Peach Blossom Stone) and does not belong to the Five-Color Stone Clays. Its color resembles peach blossoms; long-term consumption makes the body plump. Locals also use it to treat diarrhea. It was formerly abundant in Yuhang Mountain, Suzhou, but is no longer collected.

Sweet in flavor, neutral in nature, non-toxic. Primarily treats cough with rebellious Qi (Qi counterflow), Zhengjia (abdominal masses), blood obstruction, metrorrhagia (non-menstrual vaginal bleeding), expels pathogenic factors, alleviates stiffness and pain in limbs and joints, and eliminates heaviness and fatigue after overeating. Long-term consumption enables resistance to cold and heat, prevents hunger, lightens the body, and allegedly allows one to fly a thousand li, achieving immortality. Also known as Shi Nao (Stone Brain). Grows in the valleys of Mount Tai; harvested in September. Eucommiae Cortex (Duzhong) serves as its guiding herb; it is incompatible with Fritillariae Bulbus (Beimu), Acori Tatarinowii Rhizoma (Changpu), and Ferrum Depressum (Tieluo). Nowadays, people generally refer to it collectively as Taiyi Yuyuliang (Taiyi Yu Rest Grain), specifically identifying it as Yuyuliang (Yu Rest Grain); few recognize "Taiyi" anymore, although their therapeutic effects are similar. *Xianjing* frequently employs it, and Sizhen Wan (Four-Guard Pill) is also collectively named Taiyi Yuyuliang.

[Verification] When Taiyi Yuliang and Yuyuliang are initially within the shell and uncondensed, they remain yellow water, named Shizhong Huangzi (Yellow Child within Stone). After prolonged condensation, various colors appear: some green, some white, some red, some yellow. As years pass, it turns red; gradually changing from red to purple, both stages are called Taiyi. All colors are collectively referred to as Yuliang. Currently, none can be obtained from Mount Tai; however, they are available in mountains such as Kuaiji, Wangwu, Zezhou, and Luzhou.