Does look like Jasper, but I'm sure it's not. It is a piece of gneiss as Charlie said. No telling how it got to where you found it. The only forms of gneiss I'm aware of found in Iowa are from the glacial erratics from the ice age. https://archive.inside.iastate.edu/2005/0311/rock.shtml Guess you could say you found a piece of Canada in Iowa.
It looks like maybe you have glacial till. Rocks pushed in front of a glacier until it stopped and receded.So you could have a lot of rocks not native to your area.