1987 D Lincoln Memorial Cent - What Is And How Does This Happen?

I thought that was an indication that the die was getting worn out...there is some Die Deterioration Doubling on the right side of the numbers in the date, too.

See the faint doubling around the numbers and mint mark? It almost looks like a reflection. Die Deterioration is the cause.

Someone throw me out at first if I'm off base.

I didn't even notice that was a different coin.

The 1987 still has the effect on the right side of the numbers, although it is more subtle.

The mark on the outside edge is where the plating was split during the strike. A some time the area starts raising as the zinc is exposed.

The mark under the mint mark is caused by a rough edge when the die was punched making a fin on the die. After several coins are struck it eventually flattens down in time.

The die isn't worn on this coin. The striking pressure pushes the planchet and makes this appear.

So just a normal coin.

I'm not sure if I'm following you, coop.

What do you mean by the striking pressure pushes the planchet?

I understand the plating splits during the strike, but does it leave the mint looking like the coin above? Or does it leave with just the split plating and begin to raise after time?

Coop, the shadowed doubling also appears on the top of the letters near the rim (top edge of inside of "U", for example). You don't think this is because of Die Deterioration?

So this would not come out of the mint raised up around the split - over time the zink pushes up and makes these lumps and bunps? I would assume moisture would be a factor in this but then again I don't know.

Thanks all
Brent

The low swelling just inside the rim is an expression of Die Deterioration. The blisters above the letters are a combination of split plating and subsurface corrosion which has pushed up the copper plating.