A knap-in is a gathering of craftsman who chip (knap) flint to replicate arrow heads, spear points, knives and other implements that sustained, fed, and clothed native people for thousands of years. Some of the best knappers in the U.S. will be here to demonstrate how ancient-made tools and knapping have become a beautiful and collectable modern art form. See flint and chert from the U.S. and some of the most beautiful; Ohioâï¿½ï¿½s official gem stoneâï¿½ï¿½Flint Ridge flint. Visitor are welcome to watch or try a hand at knapping. Finished items will available for purchase. Free; finished items available for purchase.