From back in 2014, here’s this look at the process of alchemy, and some of the things it did for contemporary chemistry and materials science:

…in the 1980s, some revisionist scholars began arguing that alchemists actually made significant contributions to the development of science. Historians of science began deciphering alchemical texts—which wasn’t easy. The alchemists, obsessed with secrecy, deliberately described their experiments in metaphorical terms laden with obscure references to mythology and history. For instance, text that describes a “cold dragon” who “creeps in and out of the caves” was code for saltpeter (potassium nitrate)—a crystalline substance found on cave walls that tastes cool on the tongue.

This painstaking process of decoding allowed researchers, for the first time, to attempt ambitious alchemical experiments. Lawrence Principe, a chemist and science historian at Johns Hopkins University, cobbled together obscure texts and scraps of 17th-century laboratory notebooks to reconstruct a recipe to grow a “Philosophers’ Tree” from a seed of gold. Supposedly this tree was a precursor to the more celebrated and elusive Philosopher’s Stone, which would be able to transmute metals into gold. The use of gold to make more gold would have seemed entirely logical to alchemists, Principe explains, like using germs of wheat to grow an entire field of wheat.

Principe mixed specially prepared mercury and gold into a buttery lump at the bottom of a flask. Then he buried the sealed flask in a heated sand bath in his laboratory.

One morning, Principe came into the lab to discover to his “utter disbelief” that the flask was filled with “a glittering and fully formed tree” of gold. The mixture of metals had grown upward into a structure resembling coral or the branching canopy of a tree minus the leaves.

Though best not to discount the usefulness of dreams in the advancement of science, as the Principe does later.  Francis Crick, Friedrich August Kekulé (whose dream, oddly enough, was of snakes of fire devouring their own tails), and Carl Jung (a proponent of Alchemy’s psychological efficacy) would all take umbrage.

Read the full article here: http://www.smithsonianmag.com/science-nature/alchemy-may-not-been-pseudoscience-we-thought-it-was-180949430/