Science

Authentication

When I, as an outsider, entered the art world, I imagined it would be quitte simple to obtain a proper judgement on the painting. In my innocence I thought that a Van Gogh expert would see with one blink of the eye whether the painting is authentic or not. Unfortunately I know better now.
Indeed there are experts who judge with one blink of the eye (even from photo’s). Whether their judgement is right is another question.
It turns out that also the experts regularly not agree whether a specific painting must be attributed to Vincent or not. This is not only so for new discoveries but also for work already on display in the museums. (Like the Japanese “Sunflowers” and the recently discovered “Houses near The Hague”.)

Once I read an article titled: “Who’s eyes do you believe?”
This says it all. This “Do/don’t”-situation is kept alive because one cannot prove for 100% that a specific painting is authentic. On the contrary it can be proved sometimes that a painting is not authentic.

Expertise & Science

An expertise can be described as a case which convinces everyone. Scientific research is best suited for this. Vague descriptions as “stilistic differences” are subject for discussion and therefore less suited for an expertise. These kind of descriptions are perfectly suited though to create a smoke curtain and/or obtain respect.

Van Dantzig method
The only person who has, as far as my knowledge goes, conducted scientific research on the oeuvre of Vincent van Gogh is Mr van Dantzig. For this he created a long list of specific items found in the known works. When 75% of these items are found in a painting under investigation it is assumed to be authentic. This method isn’t watertight although it gives a rough first impression.

Paint research
By utilizing research on the paints used it can be determined which pigments are used in the painting. Next it can be investigated whether these pigments already existed in the period the painting is supposed to be created. If this is not the case the conclusion is simple: “Not authentic”.
Also it can be investigated whether the found pigments are used in works of the same period. If this is the case the prove isn’t 100%, but the argument is strong. (The costs for paint research are without doubt high, this is why I can’t have “Cottage with sticks” examined this way. One also needs reference material).

Enclosed objects
When painting in the open air a number of foreign objects can be captured by the wet paint. One can think of objects like:

- Sand grains
Some time ago I saw a sand grain collector on TV. It appears that every place on earth has its own specific type of sand. With this for instance it can be proven that “Cottage with sticks” can not be painted in Drenthe. I don’t know the ins and outs of this, if anyone does, please drop me a note.

- Pollen
I received this tip from someone during the exhibition “Lost and Found”. If pollen of a certain type can be identified a lot more is known about the season and place of creation. Ábout this subject I dont know much either, your tips are welcome.

- Fingerprints
During my investigation I came across an article in the magazine Disipientia covering fingerprints in the works of Van Gogh. The Kröller Müller Museum has several works in their collection with fingerprints on it.
Also on the study for the “Potato eaters” a fingerprint is found.

In the same way one can think of brushprints. I can imagine a brush wears in a unique way so the left behind structure of the paint is also unique. This might come from far but a thorough investigation might reveal something.



DNA research
In my opinion it is probable that within limited time DNA research will surface as being instrumental in the authentification of paintings.
Detecting of the DNA seems to be a huge problem though, but this might be not the case.
In the aircraft industry plastics, which needs to be glued, are not to be touched without gloves. Why not?
Because on every object one touches a small amount of grease from the skin is left behind.
In the case of a painting the carrier is manipulated by the painter before starting to paint. The grease will most probably be covered later on by the paint. This doesn’t have to be an obstacle though.

The remaining questions are:

1 – Can the grease from the skin be obtained from beneath a layer of paint without serious destruction?
I think this is possible with microscopic needles.

2 – Is the amount of grease obtained this way sufficient to isolate the DNA?
I can’t answer this question (yet).

Cottage with sticks & Vincent van Gogh - by Carl & Ans 2003-2005.

The Yasuda sunflowers


Houses near The Hague


Mr. M.M. van Dantzig
(1903-1960)