Skip to main content

Table 2 Preparation of the references for the iron-polyphenol complexes

From: New insights into iron-gall inks through the use of historically accurate reconstructions

  Water/mL Polyphenol FeSO4 Gum arabica Polyphenol:FeSO b4 Final pH
Gallic acid 40 2.35 mmol
0.442 g
2.35 mmol
0.65 g

0.221 g
1:1 1.66
Ellagic acid 40 2.35 mmol
0.710 g
4.67 mmol
1.3 g

0.355 g
1:2 2.21
Digalloyl glucose 1.75 0.103 mmol
0.005 g
0.103 mmol
0.028 g

0.002 g
1:1 2.86
Pentagalloyl glucose 2.24 0.132 mmol
0.0125 g
0.264 mmol
0.073 g

0.006 g
1:2 2.09
Tannic acid 20 1.16 mmol
1.99 g
2.35 mmol
0.65 g

0.65 g
1:2 1.49
  1. aThe ratio of gum arabic was based on the medieval treatises, where the galls:gum arabic ratio is mainly 1:0.5
  2. bThe ratio is in molarity and was normalized for the polyphenol concentration