Alchemical confusions in pharmacy: BLACK/NIGREDO

The adoption of alchemical terminology in the field of apothecary has also led to numerous confusions, completely settled only in the end of the nineteenth century.

One example related to the concept of BLACK or Nigredo.

Oleum petrae nigrum, literally "black rock oil", designates in the field of apothecary black petroleum, a sticky and foul smelling substance. In pharmacy, where the alchemical symbol of oil has been preserved (three circles in a triangle pattern, symbolizing three stacked stones), the substance is liquid bitumen from the region of Germany, recommended against scabies, menstruation problems, hysteria, fever, toothaches, parasites etc, and it was mainly for external use.
Still, nigredo was also the first stage of alchemical transformation, the process of putrefaction or decomposition, starting from the so-called black stone. In alchemy, all processes / transmutations of matter started from the raw matter, the black stone, assimilated to Saturn and lead. The foul smell and dark color of the apothecary substance might have also stressed the resemblance with the alchemical process in question.

Painted signature of an apothecary jar preserved at the History of Pharmacy Collection in Cluj-Napoca: OL(eum) Petrae Nigr(um) - Black rock oil.

Alchemical and apothecary symbol for oil.

Alchemical engraving depicting Putrefactio or Nigredo

Discover more connections and differences between the two late medieval/early modern sciences by visiting the Pharmacy and Alchemy (Farmacie si Alchimie) temporary exhibition at the History of Pharmacy Museum in Cluj-Napoca, in Unirii Square no. 28.