Just wondering if this dime is missing a clad. I'm not too familiar with clad errors. As always, any info is great and it helps me learn a little more! Thanks!
Looks like environmental damage (toning) to me. The coin could have been buried in the ground for a time. (Lots of dug clad coins look like yours.) Your best bet is to weigh your coin. If it weighs the same as a normal clad dime chances are that it is a normal clad dime that has heavily toned.
