Milk spots. Something got on the blank before striking or on the coin after striking and has corroded the silver. The whitish circles are the expansion of oxidation from the off-gassing reacting with the silver, like bacteria on a petrie dish. It has eaten into the silver and can't be removed.
Corrosion around spots of organic matter sittng on the coin. The decay products from the organic matter create circular regions around the matter. Often the result of droplets from a sneeze or cough. (You can see the droplet remains in the center of each circular spot.) They are not milk spots.
They're not milk spots. I think to highly of this forum to ask about milk spots. Here's a closer look. There's something else going on here. I was hoping someone might recognize the hallmark of a Mint process, machine, tool, or part that could cause the damage seen in the exact center of these two perfect circles of similar size.
Not the result of a mint process (unless you consider a mint employee sneezing to be a process) See my post immediately above yours.
There is nothing in the minting process that would cause this - it's either spittle from someone coughing on the coin before it was put in the plastic capsule, or some other source of liquid on the coin, after it was struck..
