Youth and science

Look into the depths of time under the dome of the cathedral

Ending. Start at No. 15

Part two. Dubna, FLNP

From the letter of thanks from the Directorate of ISRAA to JINR Director Grigory Trubnikov:
"...we express our gratitude to JINR for carrying out physical and chemical research as part of the restoration of the unique murals of the 12th century in the Cathedral of the Transfiguration of the Savior of the Mirozh Monastery (Pskov). ...The technique applied by the JINR staff brought the knowledge about frescoes to a fundamentally new level that allowed to see the picture of the ongoing processes in painting in the most complete way."

"This is a letter of thanks from the Directorate of the Interregional Scientific and Restoration Artistic Administration (ISRAA) that was sent to JINR Director Grigory Trubnikov after our first joint work in 2021," Head of the Neutron Activation Analysis group of FLNP A.Yu.Dmitriev begins his story. "Specialists of ISRAA are trusted with the restoration of the most important, most significant monuments not only in Russia, but also in other countries, for example, in Belarus.

Our group is engaged in neutron activation analysis, neutrons are our main working tool. We carry out research at the IREN facility and at the IBR-2 reactor. Since the reactor is temporarily shut down, we partially transferred neutron activation analysis (NAA) to Kazakhstan at the Institute of Nuclear Physics. Many samples were irradiated there last year, for which we are grateful to our colleagues.

We started our work with cultural heritage sites from the investigation of fragments of glass bracelets that had been found at the excavations of the Dubna settlement. Our task was to find out where they had been made. The task turned out to be easy, because in those days glassmaking had been a high-tech industry. There had been a few glassmaking centres and each had had its own recipes. Comparing the elemental composition of our samples with the prescription norms of different centres of Western Europe, Byzantium, the capital and provincial centers of Ancient Russia, we found out that all 10 fragments were of own production - half of the capital, half of the provincial. Afterwards, we came to grips with the investigation of the elemental composition of archaeological ceramics in cooperation with the Institute of Archeology of the Russian Academy of Sciences.

We often use the word for the first time in our publications. Before us, at least on the territory of Russia, no one has studied the elemental composition of the plaster bases of wall paintings using NAA. This is a sensitive technique, so sensitive that when preparing samples for irradiation, the main task is not to stain them. At the end of 2019, the first international workshop "Investigation of cultural heritage sites using nuclear physics methods" was held at JINR. By the way, the third meeting will be held in Tashkent this year. The first was attended by Doctor of Art History, an employee of the State Institute of Art History T.Yu.Tsarevskaya. She made a report on the issue of the rebirth of the color of fresco painting. She brought some fragments of frescoes with her. And from that moment on, we came to grips with the investigation of medieval murals.

We realized that only elemental analysis is not enough to study fresco painting. Firstly, it can have several layers and in elemental analysis using NAA, we cannot always separate these layers. Secondly, the result of elemental analysis is a list of those elements that are part of the test item and often this is not enough to answer the questions of art historians, restorers and archaeologists. It is necessary to know in which molecules the detected elements are combined, in which minerals they are included. This requires additional techniques that we began to master in 2019. We have been able to acquire instruments for molecular analysis: infrared and Raman spectrometers, as well as various microscopes, since we often examine samples with the size of a grain of dust. The members of the group were trained to work on the new equipment at Moscow State University and at St. Petersburg State University. In addition, we studied with leading experts in the field of painting research at the State Research Institute of Restoration. We need such certificates to confirm our competence in the field of painting research.

Today, such investigations are obligatory for restorers: before any restoration project is approved by the Ministry of Culture, it is necessary to provide the results of physical and chemical research. This requirement is logical because the restorer in his work, for example, uses solvents in order to remove late layers and contamination. In order to choose the right solvent and not spoil the subject of research and there have been such cases, one needs to know what the paint layer consists of. We have already taken part in the preparation of two projects for the restoration of the famous Pskov monuments: theTransfiguration Cathedral of the Mirozhsky Monastery and the Cathedral of the Nativity of the Mother of God of the Snetogorsky Monastery.

But restoration is the practical side of working with frescoes and there is also a scientific side - the rebirth of color. If you go to the church in Veliky Novgorod, painted by Theophanes the Greek, you will see that the images are black and red, almost monochrome. Until now, art historians have been pondering the question: is it the author's ascetic palette or the result of environmental influences - high temperature as a result of a fire, ultraviolet radiation, humidity, repeated temperature changes from plus to minus? Issues relating to this particular monument, the Church of the Transfiguration of the Savior on Ilyina Street are in the process of being resolved. But there are also particular results on this topic. First, we carried out a temperature experiment and compiled a scale of temperature transitions of primary colors and at present, we know which color changes at what temperature. On the basis of these data, we carry out a digital reconstruction of individual fragments of frescoes and obtain the approval of art critics. Currently, we prepare the first publication on this topic.

Our investigations of the fresco depicting the three apostles from the Church of Simeon the God-Receiver of the Zverin Monastery of Veliky Novgorod showed that under the influence of temperature, yellow ocher turns into red in a matter of minutes. We spoke about the results of our research to the art historian T. Yu. Tsarevskaya. Then, she began to deal with chronicles and discovered that not far from this fresco there was a wooden porch. The chronicle notes that in 1471, when Ivan III conquered Veliky Novgorod, the church was "burnt". From my point of view, this is a rather striking example when the humanitarian and natural science areas find a common language and our joint activities produce such remarkable results. I want to emphasize that this is not just a conclusion, but a conclusion supported by a physical and chemical experiment."

"There is another example of the rebirth of color," O.S.Filippova joins the conversation. "In the drum of the Smolensk Cathedral of the Novodevichy Convent in Moscow, three archangels are depicted - in yellow, green and red robes. The first two folds are drawn in white and on red clothes the folds are black. When we examined the elemental composition, we found out that there was a lot of lead in these black stripes. Therefore, white lead or lead carbonate was used, a compound that is not very resistant to external influences (temperature, humidity, some types of bacteria). It eventually turns into almost black lead oxide. And there are many examples of blackened monuments - here, in Georgia, in Europe. We have shown that in our case, the black folds on the red robes contained altered white lead and the white folds on the robes of other colors were drawn with stable lime white, so they did not regenerate. Based on the data obtained, we reconstructed a fragment of the fresco, as a result of which we showed that clothes of all colors were originally depicted in the same style.

We also managed to work with a fresco of St. George the Victorious from the 12th century St. George Cathedral in the St. George's Monastery in Veliky Novgorod that miraculously survived. Currently, St. George's cloak is black-brown, with red showing through in places. We investigated the elemental composition, found a significant content of lead, so we assumed the rebirth of color. Colleagues-art historians joined in and reported what color clothes George the Victorious is depicted in, it turned out that the cloak is always bright red. As a result, it was concluded that the degenerated lead white darkened the red color of the cloak.

"Another story refers St. George's Cathedral," Andrey Yurevich adds. "Frescoes of the 12th century were preserved in the cathedral until the 19th century. Later, they decided to replace these frescoes in this way: the old ones were knocked down and used as bedding for a new, higher floor. Not so long ago, the floor was opened and tens of thousands of fragments of frescoes of various sizes were found. Some are so large that they fit the whole face of the saint. Today, the find is in the hands of restorers and they are engaged in the restoration of fresco compositions. We took part in the work with these frescoes and found that the blue used was none other than lapis lazuli. In those days, lapis lazuli was mined only in one place, in Badakhshan, on the territory of modern Afghanistan and it was literally worth its weight in gold. The occurrence or lack of lapis lazuli in medieval monuments gives art critics the right to make assumptions, for example, about the status of the commissioners of the painting. We studied the experience of working with European colleagues with lapis lazuli. So, in Italy, in one of the churches in the south of the country, lapis lazuli was used only in iconic places for frescoes and either "false blue" was used for the background - white with charcoal, or azurite. There is a huge amount of lapis lazuli in St. George's Cathedral, it was even used in background paintings! We published the results of this research in the Western journal Herit Sci. 2022;10.

Lapis lazuli was also discovered in the St. Sophia Cathedral of the Novgorod Kremlin, in the Transfiguration Cathedral of the Mirozhsky Monastery and other churches - these are cultural monuments not just of federal significance, but from the UNESCO list. Such an extensive list of monuments cannot but testify to the unique capabilities of our ancestors.

In conclusion, I want to say that we like our work, we feel satisfaction from what we do and we are glad that we are supported by Directorate of the Laboratory."

"And we are also very glad that young people come to us," Olga Sergeevna adds. "The same Natasha Glombotskaya came to us a little over a year ago after graduating from Dubna University. She studied to be a chemist, but she seems to enjoy majoring in art history. Besides Natalia, there are other young employees in the group.

Olga TARANTINA,
photo by Igor LAPENKO and FLNP