Stainless can also be magnetic, depending on the percent of Fe in the alloy. In this case thought, it appears to be steel that has been plated - looks like it might be nickel or tin though to my uneducated eye. I'm pretty certain it is not pot metal base because pot metal would not take the dent that is shown in your photo. It doesn't look quite shiny enough to be nickel to me but nickel is softer than chrome so maybe it has been dulled by the rubbing? It should not be too costly to have it stripped and replated at a local shop - it you have one.
