From a Bond County, Illinois, area collection, a 4&1/8" by 1&9/16", 3/8" thick Waubesa Adena Knife--a big piece of VERY patinated Burlington Chert. From the slight red coloration the Burlington was heat treated, iron oxides 'gave tone' to the normally white chert--and more easily knapped quality (makes the flint harder, allows for more fine pressure chipping). There is slight grinding along the stem edges, there is heavy use-wear on the blade edges and the tip. A shaft scraping indention shows down toward one barb--it gave the tool a more multi-purpose function--you can feel the use wear in the indention. How many decades back the knife was found wasn't recorded, but very (VERY) obviously a piece of flint of this size wasn't a recent surface find--it's real, period. Shipping is $9.00, and can be purchased only by check or money order as I do not use paypal-type services--Roy A.