Since an "irregularity" on a coin caused by a rusty die IS caused by the mint and is NOT post-mint damage, to me the coin should NOT be in a DETAILS holder. BUT I think the TPG's ARE justified in noting that "irregularity" on the slab. Example of a coin struck by a rusty die: Opinions?
Anything struck by a rusty die is absolutely a mint made effect, and will not result in a details grade. If it is an issue the TPGs are unfamiliar with, you might have to convince them this is typical of the issue, but it shouldn't be too hard. And, I've never seen it mentioned on the label for modern coins. I've seen it occasionally on ancients. Here is a Mexican coin I own, struck from rusty dies. The dies were polished before use, but it didn't remove all of the rust (easiest to see on the obverse, with all of the raised pimples). The polish is what gave it the nice PL finish:
If the dies are rusty I don't see why the coin would be considered "details". I have several Manchukuo coins that look like yours. I consider it part of the coin.
Ah, now I understand. I posted that pic just to show an example of a coin struck from a rusty die. The coin is NOT slabbed so there's no label to show. It is just my conjecture that a coin struck from such dies is NOT a DETAILS coin, but I don't know that for a fact. I'm just looking for a yes/no statement from someone who knows the true answer.
A coin struck from rusty dies is absolutely not a details coin. It is a genuine mint made effect, the same as a die break, die crack, cud, or clash.
I just read your post over at NGC! https://www.ngccoin.com/boards/topic/392430-diagnostic-on-silver-coins-with-rusted-dies/
That's actually a good question. There are three main things (that I can think of) that could cause a similar look: 1. Die rust 2. Planchet flaw 3. Environmental damage. The first and most obvious key, rust will have a pimply look. If it is rust on the die, the pimples will be raised on the coin (rust eats into the surface, and causes depressions in the die - low points in a die are high points on a coin). Environmental damage to the coin may have a similar rounded feel, but environmental damage to a coin will usually look sunken into the coin (the corrosion has eaten away at the coin). It may have a similar pimply texture, but it is into the surface of the coin, instead of raised. A planchet flaw (such as a lamination), is generally going to have a streakier nature - rather than discrete bubbles, it will look more like "layers." On the coin in the first post, it's interesting that the rust appears to be in a streaky nature, but the pimples are clearly raised. This coin may have been laid on its side and something dripped down its face, causing streaks of rust (purely conjecture).
This is a good example. It's actually common on the 1849-O Seated Dime. This one did not grade because of PVC issues.
The 1833 B-1 capped bust quarter typically shows die rust pitting on both faces. Here's an NGC AU55 example from my collection: