Non-Invasive Study on the Sinope Gospels

Round 1

Reviewer 1 Report

Overall, the manuscript presents an interesting study on the inks/dyes used in a unique codex from the late Antique period.  The paper is well written and offers quite thorough information on the methodology used.  Below I have listed my suggested revisions to improve the paper.

1. Abstract, line 31: I suggest paraphrasing this sentence to make clear that the purple colour was identified as orchil, which was not expected since similar investigations have shown that other purple codices contained Tyrian purple dye. Also, specifying the time periods of the codices would be valuable to the reader.
2. Introduction, line 38: Please add a brief statement explaining what is meant by “symbolic meaning” to provide context for the reader. The concept of “symbolic importance” is used again in the discussion (line 135) so it would be valuable to the reader to explain what is meant by this statement.
3. Introduction, line 44: Please specify time encompassed by this period i.e. (3^rd - 7^th century AD…)
4. Introduction, line 47: What is meant by “illuminated”? Do you mean that only 5 folios had illustrations? Also, the word “miniatures” is now more often used to describe small sculptures or models rather than paintings/depictions, so I suggest that a brief explanation is added of what is meant here by miniatures.  I think these minor changes would be helpful to readers that are new to the field.
5. In the Materials and methods, I suggest adding a brief statement on why each technique method was used in this study. Perhaps, simply highlight the differences in the sample volume probed by each technique or their sensitivity to specific dyes at the end of line 67 would suffice.
6. Materials and methods, line 74: Please define “UA”.
7. Materials and methods, line 93: Please add information about WinAxil (Company and/or trademark information …) so it’s easy for the reader to find this software if they would like to use it in their own research.
8. Materials and methods, line 94: Please define IAEA.
9. Results and discussion, line 157: Based on the spectra shown on figure 2b, it looks like there might be some counts for the Fe peak from the golden ink, albeit these seem to be very low and barely above the background counts. Thus, I suggest paraphrasing this sentence to account for those “negligible counts”.  To avoid confusion and improve the readability of the figure, I suggest the different colors are used for the spectra shown in figure 1b.
10. Figure 3, (a) Please add an arrow to indicate the dark frame being analyzed and discussed.
11. Figure 4. Please add a small insert of the full picture to show where was the magnified picture taken from. This comment also applies to Figure 2.
12. 10 Yellow: Please add a statement explaining how the yellow ochre was identified.
13. 11 Inks: Please specify how the writing ink composition was identified.  Was it determined solely based on the XRF analysis shown in Fig 1b?
14. 12 Parchment, line 226: Please verify the emission band wavelength, based on the indicator line in figure 6 (b) it seems it should be 625 nm not 525 nm.
15. Figure 6: I suggest the following revisions to these plots to improve their readability. A) Change the results for the codex from a line to open circles or at least change the line type. B) Vary the line types or colors between the different reference lines, though this change is perhaps not necessary if at least the spectra from the codex is changed to open circles. These comments apply to both figures 6a and 6b.
16. Table 1: Specifying how the colours were identified in the three different codices would be valuable to the reader, and I suggest that it is added to the table perhaps using a combination of symbols and footnotes.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

First, it must be mentioned that I am a scientist working in radiation physics, but I have never applied the described techniques myself. I may therefore not be qualified to judge details of the paper.

The paper decribes the non-desctructive examination of a 6th century codex from the French national labriary, and its color pigments. FORS, XRF, spectrofluorimetry and optical microscopy were used.

The description of the techniques and measurements is sound and clear. Standard equipment was employed, but I was deeply impressed by the thorough knowledge and experience of the authors to derive the different pigments from the measured spectra. Especially for an outsider of this specific field, the paper is a pleasure to read as a view of a different field. As far as I can tell, the coclusions are supported by the measurements, the English language needs no improvement.

To my best ability, I endorse publication in its present form.

Author Response

No response needed.

Reviewer 3 Report

line 20 and passim: I would suggest the addition of "preserved" before "artistic".

line 23 and passim: I would suggest to add the word "pigments" together with "colourants" when colours of both organic and inorganic origin are discussed. The world "colourant" usually refers to dyes and does not to pigments of mineral origin.

line 29: in case the authors are interested in the earliest identified use of lapis lazuli in Antiquity as a painting material, this was found on a polychrome marble vessel of the 5th  c. BC

line135: I would suggest to add a reference on the relationship between the symbolic importance of the manuscript and the use of specific pigments/colourants. Considering the specific historical context in which the manuscript was produced.

173: Instead of "true green colourants", I would rather suggest "natural green pigments". 

177: a recent reference on vergault would be appropriate.

181: if the authors have a XRF spectrum for red lead, it should also be discussed in the results.

189: I would suggest to stress on the use of Madder lake in Egypt mostly during the Hellenistic period rather than in prehistory, considering the dating of the manuscripts.

254: I would suggest to replace "vegetal source" with "plant species".

I would suggest to include a comparative table with all the analytical information acquired from the examination of the manuscript.

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx