Questions ARTinvestment.RU meets Svetlana Pisareva, one of the leading experts-химиков, head of the laboratory of physico-химического analysis of the State scientific-исследовательского Institute of restoration (GOSNIIR)

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ARTinvestment.RU: When for the first time in the history of painting used a detailed chemical analysis for attribution and authentication?

Svetlana Pisareva: the Practice of chemical analysis in the field of art dates back to ancient times. Napoleon I, going in a military expedition to Egypt, took with him scientists, whose task was the study of the art objects with the help of chemical analysis (22 August 1798, Napoleon Bonaparte signed a decree on the establishment in Cairo of the Institute of Egypt; its members were appointed, in addition to the Napoleon, 35 scholars from among the arrived in the Egyptian army. — AI.).

But perhaps for the first time experts-химики was officially brought to establish the authenticity of paintings during the investigation in the case of van Meegeren (H. van Meegeren). This is not too popular Dutch artist decided in the thirties of the twentieth century to write a fake, using the techniques of the Dutch masters of the XVII century. One of the van Meegeren forgeries, the painting "Christ at Emmaus" in the style of Vermeer, made a huge impression on generally accepted expert Abraham Brediusa, and he has officially confirmed its authenticity (just van Meegeren wrote nine "Vermeer" and four other "old Dutch" and received for the sale of eight paintings of 7 million guilders, or about $100 million — AI.). When the Nazis occupied Holland, under the guise of the masterpiece of Johannes Vermeer, the artist sold art lover Goering his work "Christ and judge." After the collapse of the Third Reich, van Meegeren was brought to trial on charges of collaboration and was forced to admit that deceived the Nazis, giving them a fake. To prove it, he painted another "Vermeer" right in the camera. To confirm his words were invited by the researchers, including chemists, whose task included the examination of the authenticity of the works. A group of scientists under the supervision of the Director of the Central laboratory of the museums of Belgium Dr. Koremans (Dr. P. B. Coremans) found that in these paintings there is a pigment cobalt blue, not existed in the time of Vermeer.

AI: What are the most famous in the history of art pigments?

SP: Humanity since ancient times, chose for painting certain substances, natural minerals and artificially produced compounds and to synthesize pigments people have learned by experience, not being chemists. Organic dyes are also used for dyes, they are extracted from animal and vegetable raw materials. About the pigments used in painting, mentioned in his treatise "On the rocks" Theophrastus, who lived in the IV–III centuries BC, and a method of producing, for example, white lead described by this pupil of Aristotle, did not change until the seventeenth century.

the Alexandrian Frit or Egyptian blue (calcium silicate and copper), one of the most famous and beautiful colors of antiquity, was also obtained by artificial means. The secret of its manufacture was lost in the early middle Ages, and she disappeared from the palettes of artists in the eighth century. Antique purple — organic pigment, which was obtained from the glands of marine mollusks (genera Murex and Purpura), — was used for dyeing fabrics and painting.

the Most expensive and beautiful blue pigment— ultramarine, obtained from the mineral lapis lazuli. In its structure are anions of sulfur S2−, which give it a blue color. To extract the pigment from a natural mineral is extremely difficult, so the artists of the past looking for a different replacement. For example, natural azurite (blue copper carbonate) became a favorite among the old masters. He was especially appreciated painters of Central and Northern Europe (for example, Holbein) for the rich color and low cost.

In XVII–XVIII centuries at the disposal of artists appears an analogue of the natural mineral — artificial azurite, which was neither before nor after this period. Such a short period of the existence of artificial azurite in painting gives us the opportunity, chemists-экспертам, limit the time of creating the painting. And the main thing here — to distinguish natural from artificial mineral, because their chemical composition is identical.

the System of artisanal production of pigments passed down from generation to generation until the XIX century, when the company producing not only pigments, but also finished paint.

AI: is it Possible today to make a fake of this level to fool the experts-химиков?

SP: the Level of chemical-технологической expertise now is that any modern forgery, Dating from ancient times to the fifties of the twentieth century, with absolute probability will be revealed. Even if they used the canvas or Board the proper time, the pigments and binders will be given the hype.

for Example, van Meegeren partially scraped off paint from old canvases and used them for their fakes, and then baked them in the oven to obtain a characteristic craquelure. But modern methods of analysis can establish that the composition of binders and pigments in the paint layer does not correspond to the materials of the old masters. And in historical pigments that are produced today, will inevitably present a variety of modern impurities. I wonder what van Meegeren, a scholar on the part of the pigments of the seventeenth century, in their imitations used are mainly natural pigments, including ultramarine. However, he could not foresee that the producers added in the costly natural ultramarine pigment cobalt blue, are known only from the early nineteenth century.

Today it is practically impossible not to recognize and forgery of Russian avant-garde of the first third of the twentieth century. Although, due to the fine specificity and simplified manner, things of this period are imitated quite often.

since 1980,-х years, the market began to demand the avant-garde, he began to invest, considering as a profitable investment. Of course, there are a lot of fakes. The scandalous painting by Boris Grigoriev "In the cafe" (see AI: artinvestment.ru. — AI.) has just passed the judicial examination in GOSNIIR, and I, as a chemist, had to give an opinion for the court. Analyzing the layer of paint, I found that the picture was painted using a green phthalocyanine pigment. He first appeared in Europe in 1939 and its widespread use dates to the second half of the twentieth century. In the USSR the oil paint on the basis of this pigment and all have been producing since 1967. In the picture ten years of the twentieth century this paint to be just could not. It is obvious that the technological expertise before purchasingthe paintings would protect the collector from the material and moral losses.

is Another example. Picture "Girl in garden" signed "K. Malevich" and the date "1904". According to the conclusion of the then Department of examination GTG, the thing could not be written before the thirties of the twentieth century. However the authorship of Malevich is not canceled: it is often put an early date on new paintings to represent his paintings in the historical development. In the process I discovered an unknown pigment, a compound of cobalt, but certainly not cobalt blue. Some time later I was able to establish that this compound — silicate of cobalt and zinc. It was first synthesized at the Dulevo porcelain factory in the late 50-х years. And in 1961 in Leningrad, the plant produced the oil paint on the basis of this pigment, under the name "cobalt spectral". It became clear that Malevich this thing could not write. A cobalt spectral has become a valuable temporal marker in the examination of paintings.

At the same time we must understand that the authorship of the chemists determine the difference between the Malevich and the student who worked with him, will not notice. This case expert-искусствоведа.

the most Important moment in our expert work — study original works. It is impossible to obtain comprehensive information about the art materials in the historical and memoir literature, and even in the master recipe. An invaluable source of knowledge about what colors the artists worked, — is the paintings themselves. Here is an example. I was lucky, I had the opportunity to explore the undeniable work of Pirosmani State Museum of arts of Georgia and the Museum of the East. The information about pigments and especially on the composition and structure of its famous cloths have become indispensable not only in timing but also in attribution of his paintings. Examining the Museum's paintings, I found that in his works there is no red cadmium, which caused heated debate at the examination of his works. For the first time, this pigment was obtained in 1910 in Germany, and Pirosmani died in 1918-м and theoretically in his paintings cadmium red can be present. It turned out that to obtain a red color artist mixed red organic pigment with an orange lead oxide, and this mixture is present on all of the Museum's work. Moreover, in the studied paintings not only red, but yellow and cadmium yellow. That Pirosmani did not use cadmium pigments, Ilya Zdanevich, who met with Georgian master and whose portrait was painted by the artist during those meetings, recorded in his diary: "Cadmium Nicholas doesn't know".

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AI: Is technological expertise is never wrong?

SP: In essence, technological examination consists of two stages: determination of the chemical composition of the components of the paint layer and the correlation of these data with the chronology of the use of scenic materials. If both of these phase conducted at a high professional level, the probability of error, in my opinion, minimal.

Today in the Arsenal of experts available analytical methods, which allow to accurately determine the chemical composition and structure of art materials (I want to emphasize,all these methods require the selection of microprobe). Broad use in our region have received techniques such as x-ray fluorescence analysis of electronic skaniruyushchaya microscopy with energy dispersive analysis, IR- and CU-микроспектроскопия, x-ray diffraction, and others. Especially I would like to highlight polarizing microscopy — routine method in the laboratory analysis begins. The value of this method is that the researcher sees all sample components to distinguish inorganic pigments from organic, to assess a class of minerals (e.g., silicates, carbonates, sulfates) and that is very important for the expert conclusion, this method allows to differentiate mineral pigments from their artificial counterparts — for example, to distinguish between natural and artificial ultramarine and azurite. I would like to stress that only the use of complex physico-химических methods enables to determine the chemical composition.

some experts are Often works of art using only x-ray fluorescence analysis in his non-invasive (when on the surface there is no impact. — AI.) variant, namely — use portable analyzers, allowing to determine the elemental composition of paints from the surface of the paintings without sampling. But the result of this analysis gives only the total set of chemical elements from the different layers of paint including primer. And the expert has to interpret these data, i.e. to decide to what particular chemical compound (pigment) include these elements. Besides, organic pigments are not found in such a device, and as a result — inaccurate results and loss of important information. The customer, after receiving the expert conclusion, should understand this. By the way, a portable analyzer does not define or binder.

the Second very important component of technological expertise — is a correlation of the obtained data on the composition of the colors with the time of their production. Due to the literature of different eras, today we know what materials are used in the different centuries, as varied palette of colors, composition of soils, which compounds (natural minerals artificially produced compounds, organic substances) were in use among painters. But equally valuable for experts-химиков is the accumulation of information about the real use of pigments. For example, the study of real images as we do, and abroad showed that the red sulfide-селенид of cadmium began to be used by artists not before 1920-х years, but the pigment went on sale in 1910. It is therefore necessary to create a database about the materials of painting, exploring genuine Museum and dated paintings.

In our laboratory for many years creates the database according to the materials of the authentic works of different periods. The most important examination of this database, we have published the monograph "anatomy of the Russian avant-garde. A view from the laboratory", which presents data on the pigments and soils 135 paintings by such famous masters as Goncharova, Larionov, Popova, Kandinsky, Malevich and others, This book can also be a valuable reference for experts.

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AI: are there any experts-химиков what-либо a complete reference containing all the information on historical paints and binders? We can all keep in mind.

SP: Laboratory of physico-химического analysis of the State scientific-исследовательского Institute of restoration (GOSNIIR), which I now run for over 40 years led the jury Greenberg. In 2003 he published the results of their years of research in the monograph "From the Fayum portrait, post-impressionism. The history of the technology of easel painting". It describes all the stages of the creation of the painting and the materials from the foundations to the final protective layer of lacquer used by artists across time. I can say without exaggeration: experts in our field — is actually the Bible. As the guidebook would also recommend our book "Oil paint twentieth century and examination of works of art" in 2010. In 2004 was very useful in our case book Nicholas Isto etc. (N. Eastaugh et al.) "Pigment Compendium. A Dictionary of Historical Pigments", which describes the composition and history of use as art materials a huge number of substances.

AI: Who typically are your customers?

SP: Sometimes the museums when it is necessary to clarify the Dating or the picture is on the purchase. But most of the buyers who want to be one hundred percent sure that you will have the real thing.

Interviewed by Mary Ghanians, especially for AI
photos courtesy of S. A. Pisareva