Master Geng: Chinese Alchemist Geng Xiansheng, 'Refining Snow' or Using Mercury to Extract Silver from Snow

Geng Xiansheng, linocut 9.25" x 12.5" by Ele Willoughby, 2025

Mercury is the final prompt for #printerSolstice2425, which again made me think of alchemy. It is an element the alchemists favoured and felt was fundamental in their efforts to transmute base metals into precious metals, both in western and Chinese alchemy (from whence the more familiar western alchemy emerged). Chinese alchemy (煉丹術 liàndānshù), a name which literally means a method for refining cinnabar, or mercury sulphide (HgS) focused on longevity (and alignment with Tao) . It can be divided into the esoteric "inner alchemy" and "external alchemy" focused on making elixirs. 

The earliest recorded woman in Chinese alchemy was Fang (Chinese: 方), who lived roughly the first century BCE and is credited with a method for turning mercury into silver. So little is known about her, and what little that is known is so tragic, that I opted for another woman alchemist associated with "turning" mercury into silver, ten centuries later.  

This is my hand-printed linocut portrait of a woman alchemist known as Master Geng who flourished some time before the year 975 (Chinese: 耿先生; pinyin: Gěng Xiānshēng; Wade–Giles: Kêng Hsien-shêng). According to legend, this daughter of a scholar named Geng Qian (sometimes spelled Keng Chhien),  was known from adolescence for her intelligence, curiosity and skill in alchemy. She appears in the writing of alchemist Wu Shu, in his book Chiang Huai I Jen Lu (or Records of Twenty-five Strange Magician-Technicians between the Yangtze and Huai River) written in 975. An expert in what was called "the art of the yellow and the white" (that is, alchemy), she distilled perfumes and was also known as a talented poet and magician. Her fame grew to the point that the Emperor Xuanzong (circa 846-859) invited her to the palace, where rather than being counted amongst the palace women, she was honoured as a scholar and given the title Master, as in teacher. She was eloquent, spoke with confidence and known for wearing green robes and for her skills in performing alchemical transformations in the Imperial Court. In particular, she was known for using mercury for "creating" silver. One story tells that she could even transform snow into silver. The Emperor wished to test her skills and noted that all her transformations employed fire  and enquired whether she could perform a transformation without it. 

"She answered, 'Let me try. It might be.' So the Emperor took some mercury and enveloped it in several layers of beaten bark-cloth, closing it with the [Imperial] seal; this she placed forthwith in her bosom. After a long time there suddenly came a sound like the tearing of a piece of silk. The Teacher [Geng Xiansheng] smiled and said: 'Your Majesty did not believe in my methods, but now you will see for yourself. Ought you not to trust me ever hereafter?' Then she handed the packet back to the Emperor who saw that the seal was unbroken and upon opening it found that the mercury had all turned to silver."

Song Dynasty scroll painting "Master Geng of the Southern Tang Dynasty refining snow'"

Modern chemists speculate that she might in fact have been using a legitimate chemical process which uses mercury to extract silver from ore. Likewise, her distilling of perfumes could have employed early prohibitive form of the Soxhlet process to continuously extract camphor into alcohol. Thus while alchemy differs from modern chemistry in aims and understanding, she would have been using some methods which we can recognize as scientific and can be seen as part of history of chemistry.

In her personal life she was known for her love of wine and romantic liaisons. 

My portrait is inspired by Song Dynasty paintings including one scroll painting called 'Master Geng of the Southern Tang Dynasty refining snow' and illustrations of alchemists and their tools like the large three-legged ting furnace in which medicines were prepared.

Detail of Song Dynasty scroll painting "Master Geng of the Southern Tang Dynasty refining snow'"

References

Chinese alchemy, Wikipedia, accessed March, 2025

Fitzgerald, C.P. The Horizon History of China, American Publishing Co., Inc., New York, 1969.

Gordon, Robin L. Chinese Women Alchemists, Women Alchemists 2.0 website, accessed March, 2025.

Master Geng, Wikipedia, accessed March, 2025

Maxwell-Stuart, P. G. (2012-03-01). The Chemical Choir: A History of Alchemy. A&C Black. p. 13. ISBN 9781441132970.

Rayner-Canham, Marelene F.; Rayner-Canham, Marelene; Rayner-Canham, Geoffrey (2001). Women in Chemistry: Their Changing Roles from Alchemical Times to the Mid-twentieth Century. Chemical Heritage Foundation. pp. 4–5. ISBN 9780941901277.

Xin, Yang, Barnhart, Richard M., Chongzheng, Nie, Cahill, James, Shaojun, Lang and Hung, Wu. Three Thousand Years of Chinese Painting, Yale University Press, 1997