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Bianqing (Mineral Azurite), its detailed description is listed under the entry for Lvqing (Green Azurite).

Shidan (Chalcanthite / Copper Sulfate), originally produced in Qiangdao Valley, Qiangliju Qingshan, but currently only found in Yanshan County, Xinzhou. It grows in copper mines and is obtained through mining followed by boiling and refining processes. Naturally occurring specimens are also available and are considered particularly precious. All exhibit a deep emerald-green color. It acts most rapidly when used in medicines intended to induce vomiting of wind-phlegm. It should be harvested on Gengzi or Xinchou days in the second lunar month. Su Gong stated: Genuine Shidan comes from Dongting Valley caves and Xueji Caves in Yuxiang County, Puzhou; those with lumps resembling chicken eggs are genuine. Physicians in the southern regions frequently use it today. He further explained: Over time, Shidan turns green; when broken open, its interior is also blue-green. The next best quality comes from between the copper mines of Shangrao and Qujiang; these are fine-grained with sharp edges, resembling hairpin shafts or rice grains. The commentary on Bencao states that counterfeit versions are made by knealing Qingfan (Green Alum) with vinegar. This is no longer the case; nowadays, inferior Shidan is simply mixed with Nixiao (Saltpeter) and melted together. Those that are large in size, pale in color, lacking distinct texture, and shatter into fragments without sharp edges upon impact are such counterfeits. Some may contain embedded stones; this occurs when the bedrock supporting Shidan formation is shaved off and added to the molten mixture during production, causing them to adhere upon solidification.

Yunmu (Muscovite Mica), grows among the rocks in the valleys of Mount Tai, Qilu Mountain, and Beiding Mountain in Langya. Currently, it is also found in Yunmeng Mountain in Yanzhou, as well as Jiangzhou, Haozhou, Hangzhou, and Yuezhou, and can be used in medicine. It is harvested in the second lunar month. Among the flakes, those that are exceptionally large and crystal clear are sometimes used by people today to decorate lanterns, which is a remnant of the ancient practice of using them for screens and fans. According to careful examination: Medical texts value white Yunmu above all others. However, the method described by Wei Shuqing of Zhongshan for single-substance ingestion specifies Yunmu possessing all five colors. This likely refers to what the *Benjing* calls "Yunhua," indicating that while they are the same substance, there are different varieties. One must observe their colors facing the sun and examine them carefully to determine their true nature; viewed in shade, impurities are not visible. Those possessing all five colors but predominantly blue are named Yunying and are suitable for consumption in spring; those predominantly red are named Yunzhu and are suitable for summer; those predominantly white are named Yunye and are suitable for autumn; those predominantly black are named Yunmu and are suitable for winter; those possessing only blue and yellow colors are named Yunsha and are suitable for late summer; pure white ones are named Linshi and can be taken in any season. Therefore, the pure white Yunmu used in medical prescriptions is actually just one type, namely Linshi. There were many ancient methods for ingesting the five types of Yunmu, thoroughly discussed in Tao Hongjing's *Taiqing Zhu Shi Yao Bianhua Fang*. These are recorded in Daoist scriptures, but the specific protocols and degrees of refinement cannot be fully detailed in text, so they should certainly not be taken lightly. Additionally, countries in the southwest such as Tianzhu (India) produce a stone called Huoji, which is also a type of Yunmu; it has a color resembling purple gold and can be separated and analyzed.