When rooting out art forgeries, one solid piece of evidence that a print is authentic is a publisher’s blindstamp. A blindstamp is a small embossed raised seal used by some print publishers to identify their work. Blindstamps are difficult to fake and often not worth a forger’s efforts, and forgers who often work off of legitimate prints miss this tiny detail.
Not every fine print publisher uses a blindstamp. But if they do, catalog entries for the print will often identify its presence. The first step then is to determine if a print was produced with a blindstamp.
A light held so it rakes across the surface, best if the room is dark, make these small embossed seals easy to see. Examine the back of the print the same way, since the indentations can often be more evident, especially in older prints that have been stored flat with other prints, which can lose some of the miniscule height of these seals.
Warhol’s “Birmingham Race Riot”, his third recorded print, an edition of 500, was unsigned. The print was published by Ives-Sillman. In the lower right corner there is a complicated raised seal and a work of cleaver design, in and of itself. The presence of the seal will authenticate the work.
Elizabeth Murray’s “Up Dog”, 1987-88, a rare and sought after contemporary work, can be identified on the front and authenticated with the small raised seal of ULAE, Universal Limited Art Editions.
The general rule of thumb, with few exceptions, is to determine if a publisher used a blindstamp and then to find it on a print, matching up blindstamps to known examples is good practice for a collector.
Forged blindstamps are uncommon and, though not impossible, a blindstamp is very difficult to fake, even more difficult than forging a print.