1990 Denver Roosevelt dime error

I have spotted a 1990 denver Roosevelt dime in my collection the dime have a copper reedge is thicker than most dimes it look like it been struck on a penny planchet the front of the dime about the size of a penny than it sloped down tword the back is the same size of a regular dime the dime dose not look like a clad it cold be silver i have a light gray siver surface with a deep rim i have not weighed yet but i can post more details the 1990 dever might can be a rare dime like the 1965 copper-nickle weight 2.27