Hello What I see is all normal Environmental Damage. The discoloring occurred after it left the Mint. All worth 10 Cents each
Clad coins such as your dimes can change when exposed to the environment.. Buried in soil, dirt and sand. The weather affects the Clad Layer also. He are some metal detecting examples from my collection -
I don't see any doubling The correct numismatic terminology is Doubled Die.. Not double die Here is a good website - http://doubleddie.com/58222.html