Have a look at Sarah Durn’s primer on medieval and Renaissance alchemy as it is depicted (quite accurately, apparently) in Deborah Harkness’s A Discovery of Witches.

Where many fantasy novels are complete works of fiction, perhaps inspired by the medieval period, but not in any way historically accurate, A Discovery of Witches combines the fantastical with the academic. Deborah Harkness, the author of the series, is a history of science professor at the University of Southern California. She wrote her doctoral thesis on the history of science and magic in Europe from 1500 to 1700—the same subject her protagonist, Dr. Diana Bishop (played by Teresa Palmer in the adaptation), is researching in Oxford’s Bodleian at the outset of A Discovery of Witches.

I have looked for a long time for a concise, objective, and easy to follow description of alchemy. Thanks to Dr. Burns, an actual card-carrying medievalist, I now have it!

And it looks like I also have a trilogy of books I need to read…