I have been looking to get a target toned proof cent or two. There appears to be an abundance of the 1970 S and hardly any other dates. Is this just poor searching on eBay or was the 1970 more prone to toning for some reason? Inquiring minds want to know...
I believe the packaging they were in caused them to tone that way. You can't mint with toning, it's a chemical reaction which cases the toning. I just posted this one over in the post you lincolns thread...they are pretty cool.
It's tough finding 1970-S Proof Lincoln's without target toning. That's a little bit of an exaggeration, but 1970-S is far and away the leader in target toned proofs. There are a few 1971-S Lincoln's that also have the same target toning, though not nearly the number that the 70-S has. For just plain colorful toning covering the whole coin, 1961 is the unchallenged leader.
This is the coin that got me looking. I figured it probably had to do with the material the coins came packaged in from the mint.
https://www.cointalk.com/threads/bag-of-1970-s-lincolns.88810/ Here is a thread of mine from several years ago when I went through a full bag of 1970 S ( all large mm ), and a few I sent off to PCGS came back RD. The owner bought it for face from a local bank in 1970.
