Posted 09/02/2011 10:30 am
I think it must have something to do with preparation of the planchets, but I can't speak with any authority. It could also have to do with where the copper and nickel were sourced from and what trace contaminants are in them as a result.
I've noticed other similar patterns... For instance, nickels minted at Denver since the mid-to-late 90s very often have a more brilliant, proof-like surface compared to P mint nickels. This is particularly noticeable on 2000-D nickels, which are supper-glossy, even on later state dies with mushy lettering. I've never heard a good explanation for why that is. I also get a many shiny D mint nickels from 2005 onward that have strong yellow/gold toning, mostly around the rim, which I also rarely see on P mint nickels.
I've also noticed that Mercury dimes tone differently from the different mints. Lots of D mint dimes from the late 30s and the 40s develop a certain orange/gold toning which is less common from the other two mints at that time.
I've noticed other similar patterns... For instance, nickels minted at Denver since the mid-to-late 90s very often have a more brilliant, proof-like surface compared to P mint nickels. This is particularly noticeable on 2000-D nickels, which are supper-glossy, even on later state dies with mushy lettering. I've never heard a good explanation for why that is. I also get a many shiny D mint nickels from 2005 onward that have strong yellow/gold toning, mostly around the rim, which I also rarely see on P mint nickels.
I've also noticed that Mercury dimes tone differently from the different mints. Lots of D mint dimes from the late 30s and the 40s develop a certain orange/gold toning which is less common from the other two mints at that time.
Never noticed that... does this happen just on mint-state coins?
