A rare piece of movie history is up for auction: the 1949 Oscar trophy in Best Special Effects for "Mighty Joe Young". It's expected that it will fetch a lot.Oscars are not very often on the auction block. The Academy of Motion Picture Arts and Sciences hates to see its trophies sold. However, this one is exempted from the rules because it's not personalized or engraved.This Oscar vintage trophy was awarded to Willis O'Brien for his pioneering special effects work in "Mighty Joe Young" when he turned a bunch wood, tarpaper and old toupees from a gorilla that measured 80 feet.Willis rejected the Academy's first Oscar in 1933 for his work on "King Kong". He wanted a trophy to honor his entire crew.Merian Cooper, Merian's producer, was to be presented with the statuette when 'Mighty Joe" won special effects. Merian did not get his name on the statuette because he wanted Willis to win it.He basically gave him the award by slipping it under the table. Since it isn't personalized and was not given prior to 1951, it can be sold.Heritage Auctions will auction the statuette July 16th as part of their Entertainment Memorabilia Sale. We're told that the Oscar is likely to fetch $500,000.