It depicts a reclining woman and is designed on fine, greenish silk fabric, using the watercolor technique. Attributed to Auguste Renoir and its creases show that it was adorned with fans – possibly like those the French Impressionist had actually painted.
But his experts Telloglio Foundationwhere the work is exhibited, are slightly troubled: the artist’s signature consists of his initials, which is slightly unusual for him.
So they enlisted the chemist and art conservation scientist Elli Kampasakali, which checks the “fingerprints” of a work of art by various methods: X-ray, Raman spectroscopy, electron microscopy and others. What did they show? “So far, the pigments that have been identified are compatible with Renoir’s era and palette,” says Elli Kampasakali. “However, chromatographic analyzes will also be needed in order to determine the dye material of the fabric. The investigation is ongoing. You cannot draw conclusions with an analytical technique alone.”
But sometimes you can’t even with many. This was explained by Mrs. Kampasakali at the Telloglio tribute entitled “Technical methods for detecting fake works”, which took place yesterday as part of the exhibitions “The Hidden Charm of Forgery” and “Fake (for) Real”. Important, said the chemist, is the collaboration of positive scientists and art historians. “Because if we found something that came from a period after Renoir, we would be sure that it is a fake,” he points out. “The difficult thing is when you find materials compatible with the artist, because anyone of his time could have used them. There, therefore, it needs study by art historians and curators, who will examine the touches, the intensity of the colors and the artist’s technique in general.”
“So far, the pigments are compatible with the era and the palette of the painter. But chromatographic analyzes will also be needed,” says chemist Elli Kampasakali.
The painting conservator Elena Kargioti, who participated in the Telloglio tribute, did something different. He studied six works from the foundation’s collection, applying familiar techniques, but combining them in an original way. In fact, along with the usual spectroscopic and chromatographic methods, he used one called… “Liquid Chromatography – High resolution Mass Spectrometry with a Q-Exactive Orbitrap LC-MS orbital analyzer”. The Orbitrap orbital analyzer – located at Department of Chemistry, AUTH and it is very expensive – it is mainly used in atmospheric analyses, and the conservator enlisted it in art conservation for the first time. He tasked him with identifying the protective varnishes on the paintings (with the aim of safely removing them during maintenance) and the orbital analyst did admirably.
Varnishes and solvents
“I found the characteristic markers of the mastic and damar varnishes, which were also used in the 19th century, the period when the works were dated”, says to “K” the Elena Kargioti and explains: “Orbitrap helped me identify them. Then it was easy to find with which solvents to remove them, without affecting the painted surface. We usually do solubility tests on projects and the point is not to “get” color – that’s why we do them in a corner and not e.g. in the face of a Virgin Mary. Removing the protective varnish, which after years has turned yellow, is an irreversible, risky process. So if I identify it, I can find the right solvent and remove it without “getting” color.”
On the board “Gentlemen in a Park”attributed to Giuliani Giovanni (1836-1892), Ms. Kargioti also found that the artist’s signature was entered immediately after the work was completed (it had the same cracks caused by time) and was therefore not a forgery.
