Hi I happened to find a quarter where the middle of the threaded part of the coin is dimpled in. the result is a quarter where if u look at it from a certain angle it looks like 2 thin coins 1 on top of the other. but if u look closely at the side you realise the middle of the edge is dimpled in all around. The thread is also visable on the inside of the dimple. Its really hard to explain what the error is but i also cant seem to find the definition of this error can anyone help me out? Thanks.
The edge was etched with an acid that eats into the copper faster than the surrounding copper-nickel clad layers. It's not an error.