Venetian/Byzantine artifacts destroyed by Napoleon

I watched a TLC program on Byzantium recently.  They said on the program, that Napoleon was responsible for melting down an enourmous amount of gold artifacts/relics/art, that was kept in Venice.  Aparently these melted down items were part of the loot that was taken from Constantinople after the 4th Crusade.  Not all the items have been destroyed (many are still in Venice) but I am wondering if anyone knows exactly what was destroyed by Napoleon.  Is there any record of what the items were before he melted them down and why didn't anyone try to stop him from destroying the ancient items?  He aparently melted the items down in order to pay his troops.  I considered posting this in another forum but since it involves the actions of Napoleon I decided to post it here.