My Dime

I found a dime and I am still a lot puzzled. When I started examining it I saw that it was a 1965 Roosevelt, but it seemed to be inside of a wedding band or small ring. After a little cleaning it really started to not look right. I went to the change and found a 1965 dime and got into a box of old coins to retrieve a 1964. It was obvious when compared,  my dime is smaller. A regular 1965 clad dime weighs 2.27 grams and my find weighs 2.0 grams. A Roosevelt dime is 17.9 millimeters and my find is between 16 and 17 millimeters.
So far I have not investigated by contacting an expert. I have to test the center as it seems that the ring is clad and the dime inside the ring is silver and missing a lot of detail. Here are some pictures.
May all of your trails be smooth and your treasure sites many.
Best Wishes and Good Hunting