Does it says it's a "trophy"? There are quite a few trophies in the game and some are pretty funny - some are slightly useful - and some are just pointless. try 'using' it and see what it does That's my guess if you received it from a quest.

If it's a drop from a mob (Gnarled Bear Claw), it would be a collectible used for achievements, "using" these will add it as completed for that part of the achievement, but last I heard is that there is no "use" option so it's bugged right now.