It looks like it may have some environmental issues, but I don't know if it is a cast copy or not. It also has a pretty strong die crack through the "9" and I checked all of the 89-O's on VAMWorld and there isn't one mentioned. Chris
My first reaction was counterfeit. When I looked at the closeup the surfaces appear to have have been worked in a coin tumbler or similar process. Seeing that it's heavy pretty much confirms it's a counterfeit.
