if you had a Goya in your home...
and did not know it?
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published on September 16, 2004 in the
Spanish weekly magazine El Semanal, page 54, section Conocer
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to find out if you are the unknowing owner of a work of art worth millions?
And...you dont 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!
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
pigment from animal or vegetal origin. Even more interesting is the dendrochronology
a technique that analyzes the wood of antique furniture or pictures
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 doesnt 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 pigment analysis is a very trustworthy method. The white from lead
is so toxic that more than one ancient artist died because he didnt
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
doesnt 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 doesnt 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.
(Dont even think about the cost of restoration
why the free appraisal that are carried out in the Arts
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 doesnt fatten itself with the art word,
Well, it might well be the signature, of the artist that soon wont
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 Goyas 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 spiders web to that forgotten inherited
canvas, that old rug or that piece of furniture almost devoured by termites.
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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