
To CCF, MCH69! I'm glad it helped you out.

I'll try to answer all of your questions to the best of my knowledge.
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How long does it typically take for the deterioration to start and progress to the late stages?
It's usually noticeable around at Mid Die State, which is up to 250,000 coins struck. Late Die State is up to around 650,000 coins struck. Very Late Die State is up to around 1,000,000 coins struck.
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Do the Die's get replaced at some point?
They do at some point. They either get replaced from the die being too worn down, damaged, or from having a piece of the die break off (called a
Cud). Both dies can get changed out or just one die can get changed out.
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Would this deterioration even show up on low mintage coins as well?
It's possible. It can happen if the die stays in service too long.
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I have about (100) 2025 p pennies and it looks as if this is present on some of the coins. Can this deterioration happen to this mintage knowing there is not a lot out there in circulation?
It can. The U.S Mint will try to use the dies as long as possible.
Die Deterioration can happen on any coin, depending on how long the die is used in service.
For proof coins, the dies are only used for a short amount of time. Usually around a few thousand proof coins are struck.
I hope this helps.
Errers and Varietys.