iron gall inks

Ingredients

ferrous sulfate, tannins, Arabic gum, vitriol, alum, magnesium, calcium, sodium

Preparation Steps

Original Recipe Text

The iron gall ink (IGI) was identified as having a metal polyphenol complex base (p. 9). Chemical analysis via LIBS suggests the use of a vitriol recipe for preparation (p. 15). The main ingredients identified include iron (Fe) from ferrous sulfate, tannins, and Arabic gum which acts as a binder (p. 10). Additionally, aluminum (Al) and potassium (K) were detected, likely originating from alum added as a mordant or pH adjuster (p. 10, 15). Trace elements such as magnesium (Mg), calcium (Ca), and sodium (Na) were also observed, possibly reflecting impurities in the iron ores or local water sources used during the recipe's formulation (p. 10).

Evidence

"The results showed the use of iron gall inks, plant-based dyes, and mixed paper fibers (straw and softwood pulp), suggesting a mixture of local and imported materials from the colonial period."

Remarks

The study highlights that these inks were applied to talismans and amulets produced in the 19th and 20th centuries in West Africa (p. 3). Raman spectral shifts from 1478 to 1470 cm-1 indicate potential degradation of the IGI due to the high acidity of the paper support (p. 10). In object SEM EM 24 146, the iron gall ink was found mixed with red ink in some sections of the text (p. 9). The thick application of ink in some manuscripts provided suitable spots for spectroscopic analysis while minimizing interference from the underlying paper substrate (p. 9).