This weapon overcomes Damage Reduction as a silver weapon.
Because it is made of pure silver, there is risk of damaging the weapon if it is used against an opponent wearing metal armor (ringmail or better), or a creature with natural armor or hide that is equally tough.
This silver dagger was found in the backpack of the rogue Cliven the Burgundy. Cliven had wrapped it in cloth and grabbed it as part of his get-away stash the night he stole an icon from the temple of Bane in the Enclave's Nova Vaasan embassy.