Non-Invasive Analyses of Italian “Ostrogothic” Jewellery: The Desana Treasure
, Elisa Calà 1,2, Francesca Robotti 1,2, Joan Pinar Gil 3, Simonetta Castronovo 4, Monica Gulmini 5, Maria Labate 5 and Angelo Agostino 5Round 1
Reviewer 1 Report
The paper Non-invasive analyses of Italian “Ostrogothic” jewellery: the 2 Desana Treasure by Aceto and co-workers is a very interesting example of interdisciplinary research, where scientific investigations perfectly melt with archaeological interpretation. As a general remarque, I think that some pictures of the objects (if possible) should be interesting for the reader. Moreover, when analysing low Z matrix with XRF, and transparent material with FORS, problems can arise from a small thickness of the samples. These problems can affect, in the first case, the quantitative evaluation, and in the second one the position of some bands. Please comment in the text about the indicative thickness of the gemstone and glasses exanimated in relation to the penetration depth of X-ray and of the reflected light.
In the following a few further tips to be considered.
11. In the abstract, please change “optic fibres” into “optical fibres” or “fibre optic”
22. Lines 87-88: “the collection is currently under study with non-invasive diagnostic techniques”. Further techniques? Which ones? Or you are now working on other objects from the same “collection”?
33. Lines 150-153: “Accuracy and precision of XRF data with portable equipment 150 were recently investigated throughout for archaeological glass [10] and can be considered 151 here to evaluate the quality of the elemental determinations. A precision of 3-5% can be 152 reasonably assumed for the concentrations determined in the gemstones.” I would not use “assumed”, as in the quoted work it has been calculated. Surely, as it depends on the counts obtained for the specific element, the results could be slightly different, but maybe “determined” could be a better solution.
44. Lines 163-164: “This feature suggests a recycle of Roman material.” It is not clear why. Please provide either a reference (or a reference to the next paragraph) or a short explanation.
55. Lines 265-266: please provide a reference or a short explanation for the LOD calculation.
66. Lines 288-289: “These data suggest that these garnets may have a different chronology than the objects containing Indian garnets.” This is a very interesting feature, but I can’t understand on which bases the authors claim it. Please explain.
77. Lines 300-301: there is a space between the 3 and the coma which give issues for the layout. Please correct.
88. Line 365: “It is not easy to understand when these pieces were produced”. As far as I know, the literature regarding the change in glass composition between roman and medieval periods is quite wide literature. I understand that the period is different, but maybe some hints can be extrapolated. Generally, the K2O/CaO ratio and the PbO content are quite useful, as also said in the paper (and in the quoted references). So, I suggest to change the sentence into a more optimistic one.
99. Lines 391-393 and line 422-423: please add references.
110. Line 439 and surrounding: the groups formed are not very clear form the reported graphs. Please add the third component or the HC from the first 3 PC.
111. Lines 551-552: such a high gold presence make me think to a possible recycle of byzantine coins: does this make sense?
Author Response
See attached file
Author Response File: 
Author Response.docx
Reviewer 2 Report
The work by Aceto et al describes a well succeeded analytical study of the Dana treasure contributing with information on the location and artistic and technological production of Italian jewellery from the 5th-6th centuries, as well as on its economic and cultural implications.
The applied methodology enabled the characterization and identification of most materials (gemstones, glass paste and gold alloys) and the results are well supported by the literature references.
The work is relevant for publication in Heritage after the suggested revision.
2.2 XRF
Page 3 line 120. The precision of the measurements can be estimated between 3 % for transition and heavy metals and 5 % for light elements.
Page 4 line 152. A precision of 3-5% can be reasonably assumed for the concentrations determined in the gemstones.
Page 4, line 176: As far as the elemental composition is concerned, XRF analysis showed only the presence of impurities of Fe (0.06 %), Ti (0.03 %) and Ga (0.01 %). The concentration of trace elements sometimes can be used to trace the geographic provenance of corundum gemstones, as discussed by Barone et al. [19].
Page 6 line 265. It must be noted that the LOD (limit of detection) for Mg of the portable XRF instrument used in this work is 8% expressed as MgO;
Some details on XRF analytical study are lacking. For instance, how were the different materials quantified and how was the accuracy of this quantitative methodology verified? How were detection limits determined for each material type and why is the DL table not presented? Since trace elements are fundamental for the localization of the raw materials, either a DL table or XRF spectra should be presented.
Page 8 Line 323. XRF analysis identified it as quartz.
XRF is an elemental technique hardly identifies compounds. Authors should reformulate the affirmation. Was the spectrum of quartz determined by FORS?
Page 10 line 362. XRF analysis showed that these stones were indeed vitreous pastes, according to the content of SnO2 (3.5 %) and Sb2O5 (0.8 %). The colourant was Cu2+ (2.1 % as CuO), as already suggested by FORS analysis. The content of SiO2 was very high (68.2 %).
Authors may prefer to include the content of SiO2 in the previous paragraph as it is the former of the glass.
Page 10 line 376. They were typical soda-lime glasses, with 7.3 % CaO and K2O lower than 1 % (the content of Na2O cannot be determined with the instrument used in this work)
Does it affect the other results (not being able to quantify Na2O)?
Page 12 line 424. The object 12/Ori must be considered a case apart, as the presence of iron, copper and zinc are to be attributed to the complex structure of the clasp.
What about the presence of Pb?
Author Response
See attached file
Author Response File: Author Response.docx
