In biographies, Susanne Katharina von Klettenberg (1723-1744) was a German abbess and religious writer, a friend of Catherina Elizabeth Goethe, who is noted for having helped the young Goethe during his convalescent year at home in bed (1768-69), during which period he began his studies in chemistry, particularly the work of Swiss physician-chemist Paracelsus and supposedly the chemistry or alchemical-religious work of Klettenberg herself. 
Klettenberg has been described as a Herrnhut Pietist who was profoundly affected by mystic and theosophic traditions. 
Under her direction, Goethe immersed himself in both chemistry and alchemy, studying Bavarian alchemical writer Georg von Welling’s 1719 Opus Mago-Cabalisticum, German writer Anton Kirchweger’s Golden Chain of Homer: a Description of Nature and Natural Things, and various Rosicrucian books. 
A year later, following his recovery, Goethe famously commented to Klettenberg, in a 1770 letter: 
“Chemistry is still my secret love.”
It was Johann Herder, to note, who in 1776 had recommended the Chemical Wedding novel to Goethe. 
In 1786, possibly related in some way to these studies, as Goethean scholar Donald MacLean notes, Goethe wrote to Charlotte von Stein, mentioning that he saw in Johannes Andreae’s 1616 The Chemical Wedding of Christian Rosenkreutz the making of a good story: 
“There will be a good fairy tale to tell at the right time, but it will have to be reborn, it can’t be enjoyed in its old skin.”
1. (a) MacLean, Donald. (1982). Goethe’s Fairy Tale of the Green Snake and the Beautiful Lily (pg. 46). Red Wheel-Weiser.
(b) Georg von Welling – Wikipedia.
(c) Anton Josef Kirchweger - Wikipedia
2. Gebelein, Helmut. (2002). “Alchemy and Chemistry in the Work of Goethe” (Herder, pg. 13), In: The Golden Egg: Alchemy in Art and Literature, pgs. 9-30. Galda & Wilch.
3. MacLean, Donald. (1982). Goethe’s Fairy Tale of the Green Snake and the Beautiful Lily (pg. 46). Red Wheel-Weiser.
4. Bartscht, Waltraud. (1972). Goethe’s “Das Marchen” (pg. 28). University Press of Kentucky.
● Susanne von Klettenberg (German → English) – Wikipedia.