--- In firstname.lastname@example.org
> Mike, if it's struck on a dime planchet, and the die distance is
> low enough, the strike will be strong.
Yes, whether it's a dime planchet or dime stock, if the minimum die
distance is unusually small, you'll get a strong strike. But this is
quite uncommon among the numerous nickel-on-dime planchets that I've
I think the copper ring around
> the edge may be that the copper core expanded more than the clad
> layers. Especially considering that the core is much thicker than
> clad layers, and therefore there is more material in the core, it
> seems obvious that the core would squeeze out past the clad layers,
> when not retained by the collar. Is the fissure u see simply the
> of the clad layer, where the core has risen up around the edge,
> like the coins struck thru a clipped planchet?
I know what you're saying, but this is entirely different. On those
rare occasions when the copper core does extrude past the outer clad
layers (most often seen in off-center strikes) there is no fissure.
The circular fissure seen in this 1971-D nickel, on Fred's three
wierd quarters, and on Fred's Kentucky quarter-on-dime planchet, is
quite dramatic and indicates that some overhanging metal was struck
into the coin. Exactly how the planchets were damaged or altered
prior to the strike to create this effect, I couldn't say. My best
guess is that they were severely compressed in some rotating squeeze
device. It may be a malfunctioning or improperly adjusted upset mill
(that's the most likely candidate), but who really knows?