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Fangjieshi (Calcite), its content is attached under the entry for Shigao (Gypsum Fibrosum).

Cishi (Magnetitum), grows in the valleys of Mount Tai and on the shady slopes of Ci Mountain where iron exists; it then grows on the sunny slopes. It is currently found in Cizhou, Xuzhou, and mountains near the South Sea. The specimens from Cizhou are annually offered as tribute and are considered the best quality; they can suspend more than ten needles in a chain or hold knives and utensils weighing one or two *jin*, rotating without falling, which is especially indicative of authenticity. There is no fixed time for harvesting. This stone contains pores; the interior of the pores is yellowish-red, with fine hairs on top. Its nature is warm, and its efficacy is superior. According to the *Nanzhou Yiwu Zhi* (*Records of Strange Things from the Southern Provinces*): "In the shallow waters of Qitou in the Zhang Sea, there is much magnetite. Large ships beyond the frontier, reinforced with iron sheets, often cannot pass this point." From this, it can be inferred that magnetite is particularly abundant in Hainan. Note that Cishi is also known as Xuanshi (Black Stone). However, there is a separate entry for Xuanshi below, stating that it grows on the sunny side of Mount Tai, while copper exists on the shady side; copper is considered female (Yin), and iron male (Yang). Their therapeutic indications are quite similar, but their cold/warm natures and mutual aversions differ. Su Gong believed it to be congealed iron fluid. Magnetite that lacks pores and has a pure black luster has inferior efficacy compared to porous magnetite. Furthermore, it cannot suspend needles. Currently, northern barbarians use magnetite as gifts; these pieces often have a luster but weak magnetic attraction, leading to suspicion that they are a different stone rarely used in medical prescriptions.

Xuanshi (Black Stone), its content is attached under the entry for Cishi.

Changshi (Albitum/Orthoclase), grows in the valleys of Changzi, as well as Mount Tai and Linzi. Currently, it is only available in Luzhou. Its texture resembles horse teeth, being square-shaped, moist, and jade-colored. This stone somewhat resembles Shigao (Gypsum Fibrosum), differing mainly in being denser, larger, having longitudinal grain, and being longer. There is no fixed time for harvesting. According to the *Shennong Bencao Jing* (*Divine Farmer's Materia Medica*), Lishi (Lapis Calcitae) and Changshi are listed in two separate entries, with distinct flavors and efficacies. It further states: "Lishi resembles Shigao, with fine longitudinal grain." Tao Hongjing stated: "Lishi is also called Changlishi." Su Gong said: "Lishi has yellowish-red skin and white flesh, with oblique grain, unlike Shigao. Merchants scrape off the skin to substitute for Hanshuishi (Alumen Rubrum), but both should actually be Lishi." Currently, Lingbao alchemy uses Changshi and Lishi as a single substance. The material passed down and used by physicians resembles Shigao and is indistinguishable from the Changshi produced in modern Luzhou. However, other commanderies no longer produce Lishi, and medical formulas do not show its standalone use; often, Changshi is referred to as Changlishi. Additionally, the Hanshuishi sold in markets sometimes has yellowish-red skin; it is unknown if this is truly Lishi.