[MSN] Probing Question: How can you spot a forgery? History is checkered with stories of fakes -- and people duped into believing they were the real thing.

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Probing Question: How can you spot a forgery?
Thursday, February 1, 2007
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By Lisa Duchene
Research Penn State

History is checkered with stories of fakes -- and people duped into
believing they were the real thing.

Even an artist as great as Michelangelo was not above being accused of
forgery. As the story goes, in 1496 the sculptor created a sleeping cupid
figure, treated it to appear ancient, then sold it as such to a cardinal who
-- upon learning of the fraud -- demanded a refund. The mystery over the
still-lost cupid is credited with drawing attention for the first time to
Michelangelo's sculpting work.

So how do you spot a forgery?

Think like a forger, says Baruch Halpern, a Penn State professor of ancient
history, classics and religious studies whose class "The Art and Science of
Forgery" teaches students to do just that.

"If you don't think like a forger, you're going to get scammed yourself,"
said Halpern.

Forgers are typically motivated by several things: the prospect of great
financial gain, the desire to make a statement, or the opportunity to make a
fool of a despised contemporary or play a joke on a respected one. A forger
also may create the fake just because he can, said Halpern.

Works of art or historical artifacts found at a reputable archaeological
excavation are likely to be authentic, while those found for sale in the
marketplace are likely to be fakes, said Halpern. The best rule of thumb is
"buyer beware," he suggested. When a bargain seems too good to be true, it
probably is a fake.

Even though forgers are committing fraud, Halpern suggested that their
deceit should be kept in perspective. "Really, compared to corporate fraud,
art forgery is mild. The victims are people trying to pick stuff up on the
market for cheap. It's a con game, not a massive public fraud." The best
forgers are artists in their own right, he added. He respects their ability
to challenge scholars to be better at their work.

Famous art forgers include Han van Meegeren, who swindled buyers out of more
than $25 million by copying Dutch masters like Johannes Vermeer. More
recently, Thomas Keating claimed to have forged more than 2,000 paintings by
more than 100 different artists before his death in 1984, as a protest
against art traders who accumulated wealth at the artist's expense. Keating,
a master of art restoration, understood the chemistry of pigments and, when
creating a forgery, would plant clues beneath paint layers that he knew
restorers would ultimately find. His forgeries have become valuable
collectibles in their own right.

"Forgery is always detectable," said Halpern, "Not at the moment of the
forgery, but down the line because no forger can anticipate the scientific
advances in the next 30 years. They always -- I mean always -- come to
light."

A modern analytical method called neutron activation analysis can be used to
specifically identify the materials in an object like a painting or piece of
pottery, said Kenan Unlu, professor of nuclear engineering. A small sample
of the painting is bombarded with neutrons, causing the paint or clay to
leak gamma rays. Scientists can then use those rays to identify the object's
composition at an atomic level. That information is then cross-referenced
with what is known about the available materials during the era in which the
work purportedly was created.

Forged paintings are the easiest to spot by such methods, said Halpern,
because the chemical makeup of paints has changed so much over time. A
forged pencil sketch is harder to detect, since pencils haven't changed much
over the centuries.

Halpern's favorite case is that of the Vinland Map, a parchment some believe
to be the very first map of North America. A rare-book dealer in New Haven,
Conn., purchased the map in 1957 from an Italian bookseller. A Yale
benefactor purchased it for a reported $1 million and donated it to Yale in
the early 1960s.

Scientists and historians have debated its authenticity ever since. Two
conferences and four analyses haven't definitively settled the matter. In
2002, one published study concluded that the ink appears to be modern since
it contains titanium dioxide, a chemical that didn't appear in commercial
paints until 1920. Another study published the same year used carbon dating
to conclude that the parchment is authentic. The map is now insured for an
estimated $25 million.

Halpern, who believes the Vinland Map is a fake, said it should be displayed
and the forger respected as a genius. "If you can forge something that
passes muster, then you're a good scholar," he argued. He has little
sympathy for experts whose egos won't let them admit when they are wrong.

"Everybody gets fooled once in a while," he said. "Being wrong is part of
the scientific process."

***

Baruch Halpern is Chaiken family chair in Jewish studies and professor of
ancient history, classics and ancient Mediterranean studies and religious
studies in the College of the Liberal Arts. He can be contacted at
bxh13 at psu.edu via e-mail. Kenan Unlu is professor of nuclear engineering in
the College of Engineering and associate director for research at Penn
State's Radiation Science and Engineering Center, which houses the Breazeale
Nuclear Reactor. He can be contacted at kxu2 at psu.edu via e-mail.

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