Yes Knightstown IndianaWhich Blue River? Indiana? In IL that would be called a Madison. A true arrow point. They were used from about 800 to the 16 or 1700s.
I’m surprised it’s not made from grey hornstone. Harrison Co is famous for the balls of dark grey nodular flint. It’s found in the bed of the Blue River and also south of Corydon.Yes Knightstown Indiana