Bob, I've read a lot of your posts and your comments on many threads here on tnet. While stone artifacts are not my field of expertise, in fact I know next to nothing about them, I do see we have some EXTREMELY knowledgeable members on here with decades of experience identifying rocks that have been worked by humans and are therefore an artifact. What I have noticed is you appear to dismiss all of their collective knowledge and you tell these members, with decades of experience, that they don't know what they're talking about and they need to educate themselves. You never seem to go so far as to point out the specifics of why they are wrong, with factual details, but just brush a broad stroke stating they need to learn more.
I believe that if you were to contact someone at the Smithsonian and they tell you this is not an artifact, you will also either think, or tell them that they don't know what they're talking about. So, if someone at the Smithsonian told you that this thing was not worked by a human, would you actually reconsider what you think is an artifact? Or would you hold steadfast that everyone else is wrong and needs to learn more?