1984 Dime Missing Clad Layer

I find many of these in customer bank rolls
as well as while out metal detecting.
Just the result of environmental toning/exposure etc.
Even the outer edges of the rims can be this tone/color.
Just an FYI if you roll search for silver dimes just by looking at the edges. Always check any dark colored ones.
Brown or even black. Sometimes they are silver mercs. and roo's that have been out in the wild for some time. Most are just clad but you would be surprised when you see the date
on some of those dark ones.

Most likely environmental discoloration. if you really think it might be a missing clad layer, check the weight. A dime missing a clad layer would weigh about 1.7 grams instead of 2.27.