Barely under 4&3/4" by 1&5/16', the medial ridge (max thickness) is a little over 7/16". The piece is from an older collection that was gathered in Perry and then Spencer counties, Indiana. The knife itself shows very long knapping scars which (in places) slide over the medial ridge (outre pas flaking)--is the hand-held knife pre Early Archaic, that is, Paleo, or does the flaking style simply resemble the Paleo knives? What my answer would be might be (or might not be) what someone else thinks...that's what opinions are. That said, the family (collection) DID contain one, only one Paleo point (pictured, for background purposes only--not on the market at this time), and it's a Late Paleo, barely fluted. Are they from the same site--that answer is unknown, but the flint, the variety of Indiana Hornstone, is almost identical--as is the knapping style. Therein, you have my opinion, and what I know of the knife. Examine the pics, ask any question that you think I might be able to answer. I can guarantee the authenticity, but as for classification (culture) it's an opinion based on stylistic characteristics. Shipping is $8.00, checks or M.O.s are the ways I take payments--I do not use any paypal-type payments--Roy A.