Psimythion—a synthetic lead-based mineral—was manufactured in the Greek world as early as the 6th century BCE and became a well-established material by the 4th century BCE. Described by Theophrastus (On Stones, 56), its production involved suspending metallic lead (Pb) over a fermenting liquid (oxos)( see below), a process that led to the formation of a white  powder accumulating on the surface of the metal which was scraped off. The powder consisted of many lead minerals, both soluble and insoluble, the former rinsed off in the process of washing. The result was psimythion, synthetic cerussite, lead carbonate, PbCO₃. It was the forerunner of the famous lead white (synthetic hydrocerussite), widely used in Western art in  later periods.

Ios xystos, usually translated as verdigris, involved a similar set up also described by Theophrastus (On Stones, 57). The metal was in this case a copper plate which was suspended over a liquid (tryx); the latter derived from grape pomace soaked in water  and allowed to begin to ferment. The blue green  powder that formed over the surface of copper and which was scraped off was used extensively as a pigment in the Renaissance and later periods.

Chemical analyses of ancient psimythion pellets found primarily in female burials from the 5th–3rd centuries BCE indicate that these samples contained  almost exclusively synthetic cerussite, with only minimal traces of other lead-based phases, like hydrocerussite. This raises an important question: How was near-pure cerussite consistently produced in antiquity? Recently we proposed a working hypothesis regarding the reactions- both biotic, and abiotic- that could have taken place within the Theophrastus pot.