Hello all, This caught my eye today, the pits make it sparkly in the sunshine. I have “Oh shiny” moments Is this caused by plating blisters or something more interesting than a dryer full of BB’s?
Good question.. Dimes are clad. Different process than plating. The pitting looks like corrosion to the clad layers. Probably a harsh acidic chemical. Copper plated Zinc Cents are plated. They started that process in 1982.
Since you said it was sparkly, I would say it was run over several times leaving fresh metal in the pits that catch the light. Maybe a gravel or sand parking lot.
I’d say that the pitting is too uniform for these to be caused by physically moving the metal on the surface. You’d also likely see craters around the pits, too. There is metal missing from this coin, likely dissolved in acid.
I believe it received some kind of media blasting. Looks like someone tried to remove environmental damage, or perhaps paint, and some remains. Where larger areas of the coating lifted, it created the uneven pattern you see mainly on the obverse. It seems we've have a couple mystery coins in the past couple of days.