NEW YORK (CNN/Money) -
The audacious robbers who stole the nearly priceless Edvard Munch paintings, "The Scream" and "Madonna," from the Munch Museum in Oslo seem to have gotten away clean, at least so far. The big question, though, how can they turn the paintings into cash?
Interpol, the international police agency, reports that the black market in art theft ranks fourth among international criminal businesses, after drugs and arms smuggling and money laundering. That amounts to perhaps $5 billion a year, according to the FBI.
Most stolen works are usually unknown to the public, however, because world-famous works like "The Scream" are nearly impossible to fence.
The thieves of such art works "are usually unable to sell them because of all the media attention," says Katie Dugdale, operations manager for the Art Loss Repository, a London-based concern that provides recovery and search services.
Instead, says Dugdale, ransom demands often follow such thefts. A museum or government will often pay a substantial amount to ensure the artwork's return.
Ten years ago that's just what happened to another version of "The Scream" (Munch executed four). The 1893 painting was stolen during the distraction brought on by the onset of the Lillehammer Olympic Games, from the National Art Museum in Oslo. The thieves reportedly climbed a ladder, entered through a window (setting off an alarm that was ignored by security guards), grabbed the work, and left a postcard thanking the museum for its poor security.
The thieves demanded $1 million for the painting, which authorities never paid. The negotiations, however, helped them recover the work in a sting operation three months after the theft. Three Norwegians were arrested.
Dugdale says that some well-known works may be stolen to order. That is, a collector with an overwhelming need may pay criminals to steal a specific work of art. Of course, the collector would have to derive satisfaction from anonymous possession of the piece; he or she could never display it.
An FBI spokeswoman says the bureau regards the Munch theft as "a very unusual case, because it was an armed robbery." Art thieves usually employ guile rather than brute force.
One exception was the 2001 smash-and-grab theft of three paintings, including a Gainsborough, from the Beit Collection in Ireland. Thieves plowed a Jeep through the front door of the estate that housed the paintings, then took the art and drove off.
But most art thefts, like the original "Scream" caper, seem to take advantage of inadequate security provisions at museums and galleries.
One of the most famous examples took place in 1911 when a former Louvre worker walked into the museum, saw that the room holding the "Mona Lisa" was empty of guards and visitors, took the painting off its pegs, went to a staircase, removed the painting from its frame, and walked out with it under his arm.
The da Vinci went missing for two years until the thief, Vincenzo Peruggia (who became an Italian national hero of sorts), tried to sell it. The buyer went to the cops.
The biggest art theft in American history took place at the Gardner Museum in Boston in 1990, when thieves disguised as police officers knocked on a museum door in the middle of the night. They were obligingly allowed entrance by two security guards, whom they quickly overpowered.
That haul included a Vermeer, three Rembrandts, and a Manet, and was worth perhaps $300 million. Some overtures were made to authorities for ransoming the paintings but negotiations got no results and the works are still missing.
When the Star of India, a 563-carat sapphire and a masterwork of nature, and other gems were stolen from the Museum of Natural History in New York in 1964, it was even more of a comedy of errors.
The thieves unlocked a bathroom window during museum open hours, climbed in that night, found that the sapphire was the only gem in the collection protected by an alarm -- and the battery for that was dead. So they raked up the stones, and fled the same way they came in.
The thieves were quickly caught, but not all the jewels were recovered. One, the Delong Star Ruby, had to be ransomed back to the museum for $25,000. Another, the 14-carat Eagle Diamond was never recovered, and is thought to have been cut up into smaller stones.
The Munch paintings, the London Times reported, were uninsured against theft. That's not unusual in the art-exhibition world -- the Gardner works weren't insured, either.
"Many museums can't afford the exorbitant premiums that insurers would have to charge for coverage of these priceless paintings," Dugdale says.
But as John Oeyaas, of Oslo Forsikring, the city-owned company that insured the paintings against damage, told the Associated Press, "These are irreplaceable and insurance would mean nothing."
If the theft was not made to order, the thieves may find themselves in a difficult position, unable to sell the piece, with no insurer to negotiate with, and perhaps wary of ransoming the works through the authorities.
If so, the paintings could wind up tucked away someplace under less-than-ideal conditions. Norway could suffer a permanent blow to its artistic patrimony.