Preform, point or knife?

[autographcollector11]

Found in a site known for Mississippian artifacts, but not sure if this is a knife, preform point or finished piece. I may have posted this a while ago but not sure.
Found in Illinois-any help would be appreciated.
thanks

 

[Mark Todd]

Looks like a rough/crude knife to me, too small and thin for a preform and too large for a projectile point. Nice find. What county in Illinois?