Physicists from the Joint Institute for Nuclear Research found signs of a rebirth of the color of painting in the Smolensk Cathedral of the Novodevichy Convent in Moscow: in one of the frescoes, the white folds on the clothes of the depicted archangel gradually turned black. Scientists told socialbites.ca about this.
The cathedral’s drum depicts archangels in yellow, green and red robes. The first two coats are drawn in white, and in red clothing the coats are black.
“When we examined the base composition, we found that there was a lot of lead in these black strips. For this reason, white lead or lead carbonate was used. This is not a very stable compound against external influences: temperature, humidity, some types of bacteria. “Over time it turns into almost black lead oxide,” Olga Filippova, senior researcher in the Neutron Activation Analysis Group of the JINR Neutron Physics Laboratory, told socialbites.ca.
According to Filippova, there are examples of blackened monuments in Russia, Georgia and Europe. In this case, scientists have shown that altered white lead is found in the black folds on the red clothes, and the white folds on the clothes of other colors are painted with fixed lime white.
“Based on the data obtained, we reconstructed the fresco fragment and as a result showed that the clothes of all colors were originally depicted in the same style,” added the scientist.
The scientists used a portable XRF device (non-destructive X-ray fluorescence analysis) for their study. Applying this to the painting on the wall, they make a clear analysis of elemental composition. This allows you to determine on the spot which paint is used in most cases.
Where color cannot be determined in situ, scientists turn to neutron activation analysis. An image sample is then placed in a stream of neutrons, and “transformations” occur as a result of nuclear reactions. They are fixed using spectrometric equipment, and on the basis of which experts can talk about the materials used, the exact basic composition is calculated: pigments and plasters.
Scientists, St. They have already been able to determine the true colors of the frescoes in the Cathedral of St. Novodevichy Convent. Read more about their discoveries material “socialbites.ca”.