A Russian painting possibly worth millions of dollars will be auctioned off April 13 in Moscow. Called the Black Square, the painting was created by one of Russia's most famous artists, Kasimir Malevich.

The Black Square looks exactly as the name describes it. A black square painted on a white canvas. A thin white frame holds the painting.

The square is an example of abstract art, which is characterized by shapes that do not necessarily look like anything recognizable. But to the painter, the objects represent something. The Russian artist Kasimir Malevich, who painted the Black Square, was at the forefront of this movement.

The painting was the centerpiece of a collection created during the early nineties by the Russian Inkombank. The bank later went bust, and the art collection is being auctioned off to pay bills.

But while someone may pay millions of dollars for the painting, many people just do not understand it. Georgy Nikich is a Moscow-based art critic who helped Inkombank acquire the painting. He describes a Russian security guard who worked at Inkombank and asked to see the much-talked about painting when it was first brought to the bank.

Mr. Nikich says the guard opened the specially-made carrying case holding the Black Square and gasped. His stunned expression seemed to say: "Who would want to steal this?"

Most of Malevich's work was done during the 1910s and 1920s before he died in 1935. Many of his pieces hang in Russian and international museums, including four other Black Square paintings almost identical to the one slated for auction.

Mr. Nikich suspects there are other Black Squares still to be discovered in Russia. And he says the bank nearly missed the opportunity to purchase this one.

Someone in the town of Samara called him and said he had a Kasimir Malevich painting called the Black Square. He simply laughed, thinking it was a joke. It was not until the second phone call that a group of experts went to Samara to look at the painting.

A man wearing a track suit walked in, holding a gym bag. The student did not look like a man who owned a million dollar painting. But when he pulled out the canvas and unrolled it, Mr. Nikich says he felt he was in the presence of greatness.

Relatives of Mr. Malevich hide it for years from thieves and from the Soviet authorities who hated his work.

Now finally out of hiding, it is expected to go for as much as six to seven million dollars. A lot of money, but less than it is probably worth.

This is because after the painting is purchased it must remain in Russia. According to Russian law, works of art that are culturally and historically important are usually not allowed to permanently leave the country.