Table 1 The colorimetric changes in the paper samples and iron gall ink samples were treated with geraniol, CeO₂NPs, and a geraniol-CeO₂NPs mixture, both before and after artificial aging.

Before aging

Control paper sample

90.74

0.45

2.00

-

Control ink sample

23.32

-6.74

9.54

-

Infected paper sample

89.55

0.70

3.81

2.18

Infected ink sample

17.63

0.38

1.00

12.49

Treated paper sample with geraniol

90.26

1.11

7.70

3.97

Treated ink sample with geraniol

18.35

-1.26

0.91

1.79

Treated paper sample with CeO₂NPs

90.59

1.06

6.98

3.35

Treated ink sample with CeO₂NPs

18.58

-2.72

2.43

3.5

Treated paper sample with geraniol and CeO₂NPs

90.24

1.26

7.12

3.42

Treated ink sample with geraniol and CeO₂NPs

18.15

0.25

0.82

0.56

After aging

Control paper sample

90.22

0.78

4.27

2.35

Control ink sample

24.31

-6.25

9.25

1.14

Infected paper sample

89.70

0.92

4.76

0.72

Infected ink sample

18.50

0.56

1.38

0.96

Treated paper sample with geraniol

91.24

0.92

5.95

1.94

Treated ink sample with geraniol

18.13

0.29

0.80

0.73

Treated paper sample with CeO₂NPs

91.45

0.73

5.21

1.81

Treated ink sample with CeO₂NPs

17.71

0.12

0.78

1.08

Treated paper sample with geraniol and CeO₂NPs

90.56

0.88

5.37

1.05

Treated ink sample with geraniol and CeO₂NPs

18.73

-1.37

2.17

2.09