Mysterious Frost Handbook 玄霜掌上录

The compiler is unknown.

It was probably compiled between the Tang Dynasty and the Song Dynasty.

Consisting of one volume, it is included in the Methods category of the Dongshen Section in The Daozang.

With a total of about 600 characters, the book elaborates on the method of making "Xuan Shuang" (Profound Frost).

It states that Xuan Shuang also goes by other names such as Nü Xuan Shuang (Female Profound Frost), Qiong Jiang (Jade Nectar), Yu Ye (Jade Fluid), Di Mu Ru (Earth Mother's Milk), Gan Lu Jiang (Sweet Dew Syrup), Jiu Zhuan Yin Dan (Nine-Cycle Yin Elixir), and Ti Hu Su (Ghee). The production method is roughly as follows: Take two jin of lead, pound it into fine powder in a pot, add half a jin of mercury, stir thoroughly to form pellets, place them on a vinegar bottle in a sun-facing pit, and cover with paper and a porcelain bowl. After being heated for seven days, "a layer like heavy snow hangs upside down" on the pellets, which hardens when exposed to wind. When one jin is collected, add sweet syrup to a porcelain bowl, grind the mixture into a paste-like consistency, and steam it nine times in a zeng (steamer). Then put it into a mature silk bag, soak it in clean water, and shake it in a silver vessel for one fu shi (approximately two hours). Cover the vessel mouth with water-moistened cotton, dry it in the sun, sweep off the powder and grind it finely—it looks like spring snow and tastes sweet and delicious. Form pills with honey the size of paulownia seeds, take five pills a day, and after taking them for a year, "one will be immune to all diseases and not feel thirsty even in summer." The formulation of Xuan Shuang reflects the application of Five Elements theory in Taoist alchemy, embodying the unique pursuit of health preservation and immortality in traditional Chinese culture.