What if you had a Goya in your home...
and did not know it?

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Article published on September 16, 2004 in the
Spanish weekly magazine “El Semanal”, page 54, section “Conocer Arte.

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How to find out if you are the unknowing owner of a work of art worth millions? And...you don’t know it! Sometimes, forgotten in our attics lay asleep authentic jewels of art. These scientific tests will verify if you are in front of an original, or a fraud!

By Carlos Manuel Sanchez.

It may seem impossible or incredible, but the cases of valuable works of art that “appear” by casualty are in fact much more frequent that one would imagine. Sometimes they have been discovered while they were transferred from one hand to another, other times while “digging” in that old trunk…The truth is that whenever doubts exist the important thing is to “date” the piece and for that it is fundamental to perform both a historical and a style search on the piece.

In these cases the Museum “experts” often ask the scientist for help, whose techniques to uncover or discover the tricky and falsified ones, essentially, do not differ from those used by the forensic technicians in a morgue. One of the most generalized methods to properly “date” and authenticate a piece of art is to X rayed it, either with the mentioned type or the “beta” which are the most sensitive to light.  This system allows to verify, for instance, if traces of mercury appear in a dusk or vermilion (a very bright red), which will coincide with a landscape painted in the first quarter of the XVIII. Nevertheless, this technique has a little drawback as usually you must take a sample of the canvas, which will force us to cut a little piece of it, of course, logically it is always intended to destroy the minimum possible.

Ultraviolet light, on the other hand, informs about the presence of retouches and previous etching in an original painting. If someone has retouched it, dark patches will appear. By this means one can know if Rubens bothered to finish a painting or if he delegated the final details to any of his apprentices in his workshop. In such a case the appraisal of the canvas can drop by several millions of Euros. The infrared analysis also reveal previous etchings and “pentimenti”, changes of opinion on the part of the artist and they are useful to verify if the finished work, or a portion of it has been painted “alla prima”, that is directly and without any pervious etching or silhouette.

Another classical method for dating is the analysis with “carbon 14”. The amount found of this isotope diminishes in the dead tissues at an exact rhythm (it is divided by half every 5.730 years).

This system is only applicable to organic residues like wood, paper or…any pigment from animal or vegetal origin. Even more interesting is the “dendrochronology” a technique that analyzes the wood of antique furniture or picture’s frames and it is done by measuring the width of its annual concentric rings growth. Very accurate with oak and pine, but gives little calculation mistakes with other types of wood.

Thanks to the “Raman effect” (determined by the normal optical properties of the atoms or molecules) one can bombard a canvas with a laser and thus imprinting a sort of “molecular dactyl (digital) print”.

This is the way to distinguish the pigment and varnishes of each of the Masters. This procedure has the advantage that it is not a destructive technique and allows the analysis of particles which diameter is inferior to a thousand of a millimeter, where certainly the magnifying lens of the scholar doesn’t reach…

A classic painting is composed of four layers. The foundation to prepare the canvas, the background, the pictorial film and the varnish.  The falsifier must be able to imitate each and every one of the stratus if we want not to be unmasked by the chromatography test. This technique is really simple: microscopic samples are taken and heated, later their combustion gas composition is analyzed and, if acrylic agglutinants are found, the painting is posterior to 1930. That is, in the case the collector has paid a fortune for a Manet portrait he may as well start contacting the Interpol.

The pigment analysis is a very trustworthy method. The white from lead is so toxic that more than one ancient artist died because he didn’t used to wash his hands after using it. In the XX century it was replaced by the titanium white, a non carcinogen.

Now, as a complement of the pigment analysis we have the fiber analysis. In the case of paper, its place of origin can be determined by its texture, whether cotton, banana peel, etc). First rate geographical information is also furnished by the ingredients used in to fix or settle the ink (potato or proteins, for instance.) Therefore, if a Chinese calligraphy doesn’t have a small portion of rice flour over the satin paper where it is imprinted, hum.. Beware.

Monochromatic sodium arc lamps are excellent to discover hidden signatures under several layers of paint. The electronic photons sweeping microscope magnifies several thousand of times a sample and therefore helps to perform its morphological analysis s well as the topographic one., which are digitalized and stored into a data banc.

Later on the elemental analysis will determine if the “ochre” contain iron, or if the Prussian blue is really Prussian or if the black background contains mineral or vegetal carbon (coal).

The certification of a work of art doesn’t come cheap. The minimal cost of an historical or stylistic analysis is well over the 1,500 Euros (+/-2,400 USD) to which any laboratory tests have to be added is required. (Don’t even think about the cost of restoration…!). That’s why the “free” appraisal that are carried out in the Art’s and antique fairs, like that one of Madrid.
No, where is the solution to stop the piracy that is affecting the editorial and musical field so it doesn’t fatten itself with the art word, too?

Well, it might well be the signature, of the artist that soon won’t be a scribble en a corner of the canvas to become a microchip or a “DNA like” type inimitable by any falsifier. At least, in theory.

The casual finding of two of Goya’s non catalogued paintings has sharpened the art galleries, museums and private collectors. The polemic and controversial theme has transcended the small world of the actions and has induced many non-believers to wonder if it would be worthwhile, after all, to dust and shake the spider’s web to that forgotten inherited canvas, that old rug or that piece of furniture almost devoured by termites. Who knows…?

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For further information about Goya authentication research, view our information on the work of Prof. Perales here. Also be sure to see the web site goyadiscovery.com