I also found these while walking thru my daughter's newly tilled garden in Bourbon County, Ky. I know one is a cutting tool. The other seems like a piece of pottery. There were also bone pieces where I found these. OhioDeb
I'm guessing you have a scraper and the other piece looks like a charred rock to me, hard to say for sure though. Pottery is usually somewhat on the thin side. Did the bones appear to be blackened? The garden might be a campsite! Some nice artifacts have been found in Bourbon County for sure.
Small hill, close to water....sounds like a great location. I've found several pieces of pottery with one side blackened, can you get a picture of the center section of that piece? If it's pottery, we might be able to see tempering if any.....