The Paleo (Clovis, I'm assuming) knife has been in my personal collection for some years, originally from northern Illinois--the finder marked the piece as coming from the Utica, Illinois, area--LaSalle County. It takes but one look at the super-long flakes to identify the piece as Paleo Culture. Later cultures, Early Archaic and on to more recent times, they didn't make those long flake scares. The knapping term "Outre pas"--over-the-top--may not really apply here as there isn't a medial ridge to be noticed, both faces fairly flat. The chert is in the same category as Joliett Chert, a dull chert with fossil inclusions that are higher in luster--close as I can type the material, anyway. The max thickness is 7/16" right in the center of the blade--there were multiple thinning flakes struck from the basal edge to enhance hafting the knife, very slight basal edge dulling which may be intentional OR the result of slight movement inside the bindings used to secure the knifehead--the flint wore along the basal edge as it rubbed the handle. Every detail is lifetime guaranteed authentic, every detail. Shipping is $7.00, checks or M.O.s are welcomed. Sorry, I do not use paypal--Roy A..