Identity and purity of historical remains of inorganic pharmaceuticals from the eighteenth century

Sixteen specimens of historical remains of inorganic pharmaceuticals dating back to the eighteenth century were analyzed by a combination of spectroscopy (ICP–MS, atomic absorption/emission, UV–Vis, infrared and Raman), capillary zone electrophoresis, and chemical methods (titration and gravimetric analysis). The results obtained confirmed the identity of 14 of the specimens analyzed. With the exception of one, impurities were found in all specimens, often at relatively high concentrations. Based on these impurities, it was possible to confirm the origin of six substances as naturally occurring minerals. The other specimens were probably prepared by period apothecaries or artisans through chemical reactions. In two specimens, a recipe of the time, based on the ignition of metal with sulfur, could be confirmed. For anatron , a substance that originated as a by-product of glass melting, it was possible to determine its composition as a mixture of alkaline sulfates, carbonates, and chlorides (the first such analysis described in the literature). On the other hand, for two specimens, it was found that the substance was mistaken for a completely different compound than would be expected from the Latin inscription on the apothecary jar. Graphical abstract