The Walters Art Gallery in Baltimore has opened an exhibit that trumpets its inclusion of forgeries to make a point: that forgeries now constitute as much as 60% of prints, paintings and artifacts bought and sold. The exhibit points out how difficult it is at first glance to determine the true from the false; on display are more than a dozen works purchased at high prices and believed to be original. "Caveat emptor. Let the buyer beware," said Gary Vikan, curator of the exhibit. Vikan said museum curators are usually able to tell the difference between fakes and originals, but often only by close observation, comparison and scientific tests.