That particular diamond wasn't valuable because of it's (theoretical) retail value, but because of it's historical value to the austrian people. Which makes the

That particular diamond wasn't valuable because of it's (theoretical) retail value, but because of it's historical value to the austrian people. Which makes the heist even more unsympathetic: the thing he stole had some value to the people he stole it from, but no value to himself. He could easily have dropped it somewhere undetected, but he just didn't care enough to do it.