I don't have many colorfully toned coins, but I had to add this one to this topic. It's a details coin and the colors are questionable at best. I missed this neon buffalo for years because of the scratches and the fact that the toning looks black to the eye. It's only when you light the coin with photographic lights that the colors emerge.
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"Shine, shine, a Roosevelt dime All the way to Baltimore and running out of time" - Tom Waits 'Clap Hands'