Some ancient user-Late Archaic Period is my assumption based on the cultures that made Plummets, spent a lot of time grinding, polishing this stone ( a low grade Hematite, I'd describe it, based on the density/ weight). Length is slightly under 2&1/2" by 15/16" 'high' at the center, thickness of 13/16". The finder was living in my area, but hunted three states--here in Indiana, along the Ohio River in both Kentucky, and down into deep southern Illinois--he left no provenance to say where he found the piece, but a lot of his material I learned was from western Henderson County, Kentucky--that county is my "best guess"--Alzey, Kentucky, area--RICH in artifacts, there near the Wabash River/ Ohio River confluence--and about every ancient culture represented (I've hunted there many, many times), but have never had the luck to find a grooved piece like this one--do you call it a boat stone, a plummet, a fishing weight, or, well, you pick a name. Personally I do not think you put this much time into a simple net weight, so 'decoration', "Loaf Stone", some jewelry item you would wear seems the most likely answer. You decide the perfect name s it goes in your collection--what I'll do is guarantee the piece is real in every detail. Shipping is $8.00, checks or M.O>s are how I welcome payments. Sorry, I do not use paypal-type services--Roy A.