I can't help with the date but the level of water-tumbled smoothing suggests it originated a fair ways upstream/river (or has been beach-tumbled), so unless it was found on one of the great lakes it may have nothing to do with the site. Good luck!
I think you may be right. I was hoping it was colonial or native american but I was just aiming for the stars. Lol. The surrounding area was settled in 1713, so I couldn't help but try to tie the 2 together. Better luck next time haha
I have dug a good share of old terra cotta drain pipe shards but don't remember ever seeing any that was tempered with shell or anything else. Looks like some tempered material within the mix. No idea what you got though, just an observation.