Sage asked for a size comparison so here it is next to a quarter. This fresh water lake is in south Georgia. I have found several pieces of white flint while detecting in the water around here.
Or farm had a field where we found a lot of arrowheads, Mostly scrapers and chips from making them. Most were small bird points but my sister found a spear point. I don't know what she did with it because she just didn't want me to have it. I also once found a piece of sandstone with a groove in it for shaping arrow shafts. The odd part was there were no rocks of any kind on our farm. The flint had to have come from the flint hills about forty miles to the east.
Nice find. I just wish the silver coins were as plentiful as the arrowheads are where I live. I bet I have well over a 1,000 points. I was serious into hunting them for about 10 years.