Strongly patinated flint, you don't have to guess if it's real--the condition speaks for itself--put another way, this Knobbed Hardin ( or possibly Dovetail, the base is somewhat short for a Knobbed Hardin) is lifetime guaranteed real. Period. Material identification on the Kentucky piece is a challenge--similar to hornstone, but far more grainy--high in silicate, and this is a layer flint, not a nodular material--that may have helped make the preform start off thinner as the 'grainyness' would seem to be a challenge to an Early Archaic knapper--I'm not a knapper, wouldn't know how, but when I see a flint like this I assume the flintworker had his hands full. Length is nearly 3&3/16" by 1&1/16", only 5/16" max thickness nearer the base. Basal edge shows only light edge grinding, a few passes across a piece of sandstone to dull the edge. The more it was sharpened, the more triangular the blade became--tip, barbs, and basal corners are all in place, undamaged, so the condition bumps up the grade more than the flint itself would. Shipping is $6.00, checks or money orders are the way I take payment--checks are welcomed. Sorry, I do not use paypal--Roy A.