1987-D LMC - Odd MM

Even during striking the plating can be split and show this on the outside devices of coin and usually on the lower S/E of the mint marks. On the pre 1990 coins the mint marks are added to the dies with a punch. With the chisel making the mint mark deeper, it often finned the die in this area made a split the plating in this area. After striking many coins the fin wore down/flatten and the rest of the coins were normal without the split plating. On the post 1990 cents you see this less often.