Could somebody explain to me how a lamination error happens? I thought that the pre '82 penney's were solid coins. So what exactly is de-laminating? Is it a problem with the composition of the planchet?
It's "solid" in the sense of being one continuous alloy, yes. Now, let's consider how much of that alloy was needed just to produce 1942-dated Cents. According to my calculations, that number approached 3300 tons of alloy. Or, something over 150 full modern tractor-trailer loads at maximum gross weight. That's a lot of metal to produce with perfect homogeneity, and I don't think they always succeed. One can assume that there are places of improper mixing ("Woodie" Lincolns hint at this), bubbles trapped in the final product, rushed cooling leading to brittle areas, things like that. All sorts of potential imperfections which could lead to delamination down the road; indeed, the Mint preparation process could be a factor. Ain't hard to understand once you envision the scale of things.
It really does amaze we how much circulation wear some error coin get before someone notices them. Nice find.
I believe that some laminations can take years, before they show any kind of separation. I imagine that the loosening of frictionally bonded metal may take some time.
