海角大神

It's one of the biggest discoveries of Nazi-seized artwork in decades: a trove of 1,400 works of art 鈥� including a previously unknown Marc Chagall painting. The collection's total value is estimated at 1 billion euros ($1.3 billion) by the magazine that broke the story.

So why was the unusually large find kept from the public for so long 鈥� nearly two years 鈥� before the German authorities finally went public about the unexpected find?

That's what many were wondering today as Bavarian authorities offered new details about a cache of 1,285 unframed and 121 framed paintings, sketches, and prints squeezed into the dim and cluttered Munich apartment of Cornelius Gurlitt 鈥� the son of Nazi-supported art dealer Hildebrand Gurlitt.

鈥淲hen you鈥檙e dealing with Nazi-looted artwork that may belong to heirs in their 80s or 90s struggling to reconnect with their heritage, a detailed list of seized items should be posted online immediately,鈥� says Chris Marinello, the director and founder of London-based Art Recovery International.

'Degenerate' art

Authorities searched Mr. Gurlitt鈥檚 apartment in late 2011 on suspicion that he was evading taxes, Germany鈥檚 Focus magazine . But his telling history should have led them there sooner, says Mr. Marinello. Gurlitt's father was one of only four art dealers permitted by Nazi authorities to sell artwork seized from museums and labeled as 鈥渄egenerate鈥� due to Jewish or un-German associations.

The reclusive, 80-year-old Gurlitt 鈥� who has disappeared from the apartment 鈥� lived alone, and every once in awhile sold one one of his many inherited modern art pieces for extra money. A few years earlier, he received $1.17 million after putting Max Beckmann鈥檚 鈥淭he Lion Tamer鈥� on auction at the Cologne based Lempertz.

Gurlitt鈥檚 total collection was later estimated to be worth $1.3 billion, according to Focus magazine, though German authorities declined to give a total market value during a Tuesday morning press conference.

The details of the find were not made public earlier because 鈥渢he legal situation of the art is very complex,鈥� said Reinhard Nemetz, a chief prosecutor in the Bavarian city of Augsburg.

Dr. Meike Hoffmann of the Degenerate Art Database at Free University Berlin sifted through slides of famous finds, including those by Pablo Picasso, Pierre-Auguste Renoir, and Henri Matisse. First assumed to be only modern work, some of the pieces stretched back to the 16th century.

A long process

In attempts to identify the art, the Munich authorities reached out to art experts such as Dr. Hoffmann, who declined all media interviews Tuesday, and The Lost Art Database, run by Germany鈥檚 central office for the documentation of lost cultural objects.

The Lost Art Database, which works largely with art seized from Jewish owners during World War II, was contacted by Bavarian authorities in the spring of 2012, said its director, Michael Franz.

鈥淭he decision of how to run the investigation lies in the authority of the district attorney and customs office in Augsburg, and we supported them,鈥� Dr. Franz says, declining further comment.

It continues to be a lengthy process to decide which pieces of art were snatched from Jewish owners or purchased at a fraction of their value, said Mr. Nemetz.

Yet the mystery could have been more quickly resolved had the authorities made a list of pieces available sooner, says Marinello. 鈥淭here are so many organizations that specialize in researching Nazi-looted art claims that would have been happy to step up and assist.鈥�

David Rowland, a New York-based lawyer who specializes in art recovery, has been fielding frequent phone calls from some of his clients who have been seeking lost and stolen art. Their main question: 鈥淲as my artwork found in Munich?鈥�

鈥淲e have to tell them that we don鈥檛 know yet,鈥� says Mr. Rowland, a principal of Rowland & Petroff. 鈥淲e鈥檒l write to the Munich authorities on their behalf. Going forward, we hope [the authorities] will be as transparent as possible and publish a list online.鈥�

The future of restitution work

The Nazis confiscated about 16,000 pieces of art during World War II, according to the US Holocaust Memorial Museum in Washington D.C. Munich was the center stage of Propaganda Minister Joseph Goebbels 1937 鈥淒egenerate Art鈥� exhibit, which attracted over 2 million visitors.

There are an estimated 10,000 pieces still missing from Nazi plundering, and many families around the world are still searching. 聽Germany and 44 other countries were signatories of the , whose first principle reads that, 鈥淎rt that had been confiscated by the Nazis and not subsequently restituted should be identified.鈥�

Marinello is flying to New York Wednesday to meet with the prominent Rosenberg family, who had numerous paintings 鈥� including Henri Matisse鈥檚 "Portrait of a Lady," found in Gurlitt鈥檚 apartment 鈥� seized from them in France during World War II. In April, the family learned that a Norwegian museum had another one of their Nazi-confiscated Matisse paintings: 鈥淏lue Dress in a Yellow Armchair.鈥�

鈥淭he greatest impact of the Munich discovery is that restitution work is still very much alive,鈥� says Marinello, 鈥渁nd that there鈥檚 still much work to do.鈥�