Very much like VistaCruiser69s 2023 Cent, here is one that has been in circulation until I found it today. Note the Zinc looks like it is on top of the copper.
Sometimes perspective gets confusing when looking through a microscope and it becomes difficult to tell what is on top. Sometimes my eyes play tricks on me and the relief (design) looks like the field and the field looks to be in relief.
You can see the edge of the copper coming off of the rim. On top of that is where the zinc is showing and it looks like it failed to get coated correctly.
One more photo. You can clearly see the inside curve of the rim. It is covered with zinc. It makes me wonder if the zinc could have been pressed out of the center of the coin though small holes like the one in the rim directly above the T
Look at your next to photo. By the D in God you should be able to clearly see lines that come down from the room into the field of coin. That is caused by a well worn die. You can also see where the copper plating has cracked away from the coin with the zinc showing on top of it. That is what I’m talking about. It’s like it wasn’t even coated with the copper pleating to begin with.
Ok, I think I understand what you are saying. I'm thinking that perhaps the pressure of the strike (along with thin copper and/or an overused die) caused a crack in copper just next to the rim. This crack(s) resulted in the little copper shards and allowed a bit of zinc to flow out around the rim? Just a guess.
A good place to start is with the process. The process to make a planchet and the process to coin a coin. planchet - copper plating is generally homogeneous. But surface prep of the zinc substrate can influence the bond. Residue can adversely impact this ( e.g., oil, dirt, debris). coining - this process displaces material and in areas with more detail and sharp edges, the copper may become significantly thinner/stretched and more prone to cracks, splits and breaks. Looking at your specimen, there may have been bonding problems further exacerbated by the coining process. This was further exacerbated by circulation, exposure, and aging.
Synchronicity seems to be with me. I discovered this example on the PCGS site ----> PCGS#381105. The Copper plating is clearly not "wearing away". Nor is there some sort of inverted perspective in play. A crack seems to be the fault that is the source of the zinc, perhaps in combination with bonding problems and/or weak copper plating.
