Spicer,
Don't take this post the wrong way, your find is outstanding and very interesting. The "but" is that I can't see how that is a bannerstone preform. In fact, I would go so far as to say that it is not prehistoric American at all. I don't know what it is, but I have never seen an artifact like it. I own nearly every important publication on the topic over the last hundred years, and both of the Bannerstone Books (Knoblock 1930, Lutz 2000). I also have a large collection of bannerstone preforms to compare it with. Nothing like it appears anywhere in the archaeological record for Kentucky.
I know that an archaeologist told you what his opinion is, but opinions(mine included) are just opinions. I can't tell you how many times I have recieved a call from someone telling me that the archy at the museum told them they have a very rare artifact, and I come to find out is not anything like the archy described. At one point, I starting taking pictures of all the blatant errors on display at museums I visited. The problem is that arch's are never taught the forms, materials, techniques, and classes of prehistoric artifacts. The bannerstone lesson for arch's is a paragraph in a single class entitled "problematicals".
Sorry to ramble, and I certainly don't mean to downgrade the find. You can contact me privately to discuss further.
Regards,
Jon Dickinson.