Please don't misunderstand me. I was simply pointing out the similarities between your "unknown bead", as you described it, and the flasks being offered on ebay. I am posting this picture to clarify my point. These "core-formed" vessel reproductions are based on the real things! Yours could very well be the real "thing". This cannot be determined by me from the picture you provide and I am not implying it as such. As Jan pointed out, there are enough pristine ancient beads in existence, that bead "age" condition is not necessarily a determining factor and if it were, this could never be done from a photo (no matter how good) alone!
It is a beautiful bead and I look forward to seeing a great photo of it. Thanks for sharing, Thomas