carbon-based ink

Ingredients

charcoal, soot

Preparation Steps

Original Recipe Text

The writing medium is identified as a carbon-based ink, manufactured from charcoal or soot. These materials are characterized by a high and constant absorbance rate above 1510 nm, which allows them to remain completely opaque under infrared reflectography (IRR) (p. 5). The study notes that such inks were predominantly used for documentary texts in Egypt during the 4th to 7th centuries CE (p. 2).

Evidence

"Infrared reflectography showed that the inks investigated absorb infrared radiation above 1510 nm, remaining visible in the infrared images obtained. This indicates that charcoal or soot was used in their making."

Remarks

Carbon-based inks were found on the majority of the 23 documentary papyri studied. While most were 'pure' carbon, some contained trace elements like Ti, Mn, Fe, Cu, or Pb, which likely represent unintended contamination from manufacture, storage, or usage rather than intentional additives for iron-gall preparation (p. 6, 7). Three court proceedings (P.Oxy.1878, 1879, 1880) were penned with relatively 'clean' carbon ink (p. 9).