An appraisal of the Detroit Institute of Arts collection estimates the works are worth $2.7 billion to $4.6 billion. Some are suggesting the valuables be sold to help pay for municipal debts in the city's bankruptcy case.

The evaluation was commissioned by the city and the museum in preparation for a federal bankruptcy case in August. While the large amount sounds promising, the appraiser, Artvest Partners, cautions that selling the items would not generate close to the art's worth. Market conditions and currently unpopular pieces would all contribute to lower sale prices.

"A significant segment of [DIA's] collection is in areas that have fallen out of favor with collectors, and that are underperforming their market peaks in 2007," a report by the firm said. Old master, 19th-century European paintings and pre-1950s American art were among the genres not likely to garner much in sales.

Artvest co-founder and the appraiser for DIA's collection, Michael Plummer, said that liquidating the art would flood the art world, furthering dropping Detroit's potential revenue, and would eventually cause the Institute to close.

"Rather than being a source of cash to creditors or a burden on the current city, in fact, the DIA is the single most important cultural asset the city currently owns for rebuilding the vitality of the city," Plummer said.

Regardless of final sale prices, the auctioning off of these artworks would only chip away at the $18 billion of debt Detroit faces. Still, some creditors are hard-pressed to sell the works to lower what the city owes.

"The report makes it abundantly clear that selling art to settle debt will not generate the kind of revenue the city's creditors claim it will," Bill Nowling, spokesman for Detroit Emergency Manager Kevyn Orr, said.

Among the works are pieces by Peter Bruegel the Elder, Vincent van Gogh and Rembrandt.