Your dime looks to be a regular Mercury dime that was minted between 1916-1945. I don't see anything unusual about it. The 1991 cent is not steel. That is the zinc core that has had the copper plating removed or was not copper plated. I would keep all three.
In the future, please crop and rotate your pictures as per CCF instructions.
It's possible the copper plating of this 1991 cent just wore off prematurely, as does tend to happen from time to time. Regardless it isn't worth anymore than face. The 1919 cent is in about VG condition while the Mercury dime might be an F, those are my thoughts.