A poor quality photo. You'd have to get it in focus and show both sides. From what I can see, I'd have to call that one environmental damage.
Joshua, Most likely you have a normal Dime with Environmental Damage. When a dime is minted only a blank Dime planchet would be able to fit into the Dime chamber. A blank Copper Cent Planchet would not fit into a Dime Chamber so it is impossible to have an all Copper Dime.
As others have said, it is probably environmental damage. If it were truly missing a clad layer, the color would vary from red to red/brown. Chris
Letters missing because of grease-filled dies are very common and only worth something to a bidiot. Chris