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The red pigment studied contains hematite and, more frequently, quartz. The Raman spectra recorded on fine sherds from Hoiseşti and Scânteia are very similar and present the main bands of hematite. The diffuse shape of the Raman bands is caused by the fine granulation of hematite. Also, this is confirmed by high intensity peaks in the 200-300 cm-1 region and a low intensity at 1320 cm-1, which is the most intense Raman band of hematite in large crystals (Zoppi et al., 2008; Buzgar et al., 2009).
The presence of quartz is proved by the most intense band at ~465 cm-1
Quartz gives a Raman signal which is more intense than that of hematite, therefore hematite bands are less obvious in the Raman spectra.
The presence of both hematite and quartz in the red pigment excludes the use of Fe oxyhydroxides as pure red pigment. For the red color, red clay, washed several times, a process that enriched the clay with Fe oxyhydroxides (+quartz), was used. This known process is used even nowadays by pottery artisans. The source of this clay is not a special issue, as it is commonly found interbeded throughout sedimentary deposits of the Moldavian Platform.
The black pigment studied contains jacobsite. This mineral was also reported by Constantinescu et al. (2007). It is possible that it originates from the weathering crust of the Mn accumulations from Suceava county, as shown by Constantinescu et al. (2007), but we believe otherwise for two reasons. Firstly, in all samples, spectra indicated the presence of jacobsite as the only Mn mineral (absence of Mn carbonates or silicates). Secondly, several samples of black Mn corpuscles were provided by archaeologists from the “Ştefan cel Mare” University of Suceava. These Mn corpuscles were used as pigments in the Cucutenian age. Preliminary data (morphology, mineralogical composition) indicated the Nikopol manganese ore basin from Ukraine as source of these corpuscles.
For the raw black ceramic from Hoiseşti (and this sample from Scânteia), the paste used was a clay rich in organic substance. Through the firing process, the organic substance turned into black carbon. The Raman spectra of these samples clearly indicate the presence of black carbon, being similar to the spectrum of a black ceramic sample from Isaiia (Precucuteni culture).
• Jacobsite spectrum from the RRUFF project [link]
• BUZGAR N., BODI G., AŞTEFANEI D., BUZATU A. (2010) - The Raman study of white, red and black pigments used in Cucuteni Neolithic painted ceramics. Analele Stiintifice ale Universitatii “Al. I. Cuza” - Iasi, Tome 56, issue 1 [link]
• Constantinescu, B., Bugoi, R., Pantos, E., Popovici, D., 2007. Phase and chemical composition analysis of pigments used in Cucuteni Neolithic painted ceramics. Documenta Prehistorica, XXXIV, 281-288.
• Zoppi, A., Lofrumento, C., Castellucci, E.M., Sciau, Ph., 2008. Al-for-Fe substitution in hematite: the effect of low Al concentrations in the Raman spectrum of Fe2O3. Journal of Raman Spectroscopy, 39, 40-46.