Mixture of iron gall and logwood inks (Cu/Fe-GALLS/LOG)

Ingredients

logwood chips, gallnuts, ferrous sulphate, copper sulphate, gum arabic, sugar, water

Preparation Steps

Original Recipe Text

Based on Ribancourt’s Campeachy ink (p. 4): 2 g logwood chips boiled in 25 mL water for 1–2 hours in a closed beaker. Decoction was filtered and 4 g crushed galls, 2 g ferrous sulphate, 0.5 g copper sulphate, 1.5 g gum arabic, and 0.5 g sugar were added.

Evidence

"A mixture of iron gall and logwood inks (Cu/Fe-GALLS/LOG) was prepared by using a slight modification of the recipe recommended for the Ribancourt’s Campeachy ink [3] as follows: 2 g of logwood chips in 25 mL of water were boiled in a closed beaker for 1–2 h. The decoction was filtered, slightly cooled, and then 4 g of crushed galls, 2 g of ferrous sulphate, 0.5 g of copper sulphate, 1.5 g of gum arabic, and 0.5 g of sugar were added."

Remarks

Logwood was often used as an additive to iron gall inks that were not black enough (p. 2). Raman spectroscopy at 785 nm primarily detects the metal-polyphenol complex of the iron gall component, while 532 nm excitation reveals logwood markers, which is critical for identifying mixtures (p. 1, 15). Analysis only at 785 nm could lead to the false assumption that only gall ink is present (p. 17).