A base that keeps reminding me of Agate Basin Knives--there is even a bit of lower lateral edge grinding--it the piece was collateral flaked, a trait Agate Basin knappers used so well, that'd make identification so much easier--as-is, my opinion is that the knife is that Late Paleo culture (Agate Basin) but opinions are just that. Knapping, that's VERY Early Archaic in style: pressure chipping, not percussion work--edges show a considerable degree of ancient usage--VERY dull. The culture that made and used this knife got their money's worth from the Payson-type flint. Note on a couple of the pictures, the reflection of the light--that's use polish. The tip especially, it's slick to touch. Whether this knife was part of the Bond-Montgomery County part of the small collection or came from Jersey County, Illinois, wasn't clear--central west, maybe far western Illinois, but 100% guaranteed authentic: the patina is there. Shipping is $9.00 with checks or M.O.s the payment forms I use. Sorry, I do not use paypal-type services--Roy A.