Next to inscriptions and markings, imperfections represent another excellent means of uniquely identifying an artwork in case of its eventual loss or theft. Object ID calls these identifiers “distinguishing features,” and they usually consist of scratches, creases, stains, drips in paint or glaze, bubbles and surface texture that occur as “the result of a chance event during the manufacturing process or minor damage sustained at a later date.”
How to record them
When distinguishing features are present, it is best to record them in three ways: by narrative description, sketches and photographs.
Your gut reaction to the preceding statement might be that if you have a precise photograph, then why do you need a narrative description or sketch? Admittedly, a narrative description will be less precise than an image, but a written narrative is easier to incorporate into an online database than a photograph. In fact, some databases cannot accommodate high-resolution, mega-pixel photographs at all. Narrative description also has the advantage of requiring no special equipment, no photographic or artistic skills, and no need to add material subsequent to the recording session.
General Advice for Selecting Distinguishing Features
The Getty Foundation’s introduction to Object ID observes that “the nature of the object usually dictates the type of feature that should be selected” as the artwork’s unique identifier. Ideally, the feature should be large enough to be seen by the naked eye and be of a type that’s difficult for a thief to alter or remove. For example, thieves routinely remove stolen paintings from their stretchers in order to conceal and ship them. If the distinguishing feature you select to identify the artwork is physically located on the edge of the canvas or where the canvas is attached to its stretcher, there exists a high probability that your identifier will be removed, obliterated or altered during the detachment/re-attachment process. That may not only deprive you of a means of proving that a recovered painting is, in fact, yours, it could work against you by giving a party in possession (such as a high-profile collector, dealer or museum) an argument that since the painting hanging on their wall lacks your identifier, it’s not the same as the painting that was stolen from you.
Given the foregoing, care must be exercised to select only enduring distinguishing features for Object ID purposes, which may require you to imagine how a thief or black market purchaser might try to alter the artwork to prevent its identification as a lost or stolen artwork.
Paintings
The best feature to record about a painting is the artist’s brushstrokes. In realist paintings, artists strive eliminate evidence of brushwork, and this can be used as a distinguishing characteristic. By contrast, impressionist and gestural abstract expressionist works are usually denoted by distinctive strokes, the thick application of impasto, drip marks and paint splatter. Cracked paint, damage to the canvas or paint surface, losses and repairs also provide enduring features that can help uniquely identify an artwork in case of its loss or theft.
"Railway Carriages" was painting by Vincent van Gogh in Arles during August of 1888 on an unprimed linen canvas.
And don’t overlook the reverse side of the canvas or other support, such as wood or galvanized steel panel. The reverse side of a painting often contains signatures, stamps, stains or even paint that has bled through the fabric, creating a pattern on the back of the artwork. In some instances, it may even reveal an under-painting that differs from the image on the finished work. All of these represent excellent information which, unfortunately, is frequently overlooked when recording an artwork for Object ID purposes.
His first attempt was a locomotive that he scraped off the canvas before starting over and painting the railway carriages depicted above left. This under-painting serves as a unique distinguishing feature for Object ID purposes.
In addition to irregularities at the edge of the canvas and at the periphery of the paint, it is also unwise to rely on restorations as the sole means of identifying an artwork. Whereas edge features can easily be removed, obliterated or altered by cutting down the size of the support, restorations are likely to change over time. Moreover, good restorations are normally invisible to the naked eye making it impossible to describe them by narrative or adequately capture them on film.
