My $2 caliper reads a full 5" by 1&11/16", a max thickness of 13/16". The material is a tan Jasper--an Ohio River beach-found piece of Jasper (see the brown cortex) that the river carried from the eastern mountains here to Vanderburgh County, Indiana.--likely the piece is Mississippian Culture, around our year 1400 +/-, a dugout canoe-making tool if you study how the bevel on the tip is designed (and use polished). Aside from the Adz-type bit, note the super heavy polish on the heel--polished so the tool wouldn't cut into the user's hand. An interesting feature in how the piece is made is that one edge has large 'rasping' flakes while the opposite side has small pressure chipped "fine scraping' flake scars. How many, many hours this 'woodworking tool' was in someone's hand would be interesting to know--a dugout canoe isn't a couple hour project. Neat piece, in my collection for fifteen or more years--enjoy it (in your collection) if you get the chance. Shipping is $10.00 due to the weight. I accept checks or money orders, but I do not use any sort of paypal-type service--Roy A.