This way they stay natural
I always give my raw coins a quick soak in acetone to remove any unseen PVC residue or other contaminants before storing (I usually use 2x2s or Saflips.)
What he said plus a controlled environment i.e., low/lower humidity. Last year, my father asked me to get his recently deceased wifes huge stamp collection appraised. The very first U.S. stamp released, a Ben Franklin, was in it. Two apprasiers said much of it, if not all, was ruined due to getting wet or exposure to excessive moisture. The glue on the backs was mostly gone. I haven't seen mention here of the best humidity level for coins but I keep desiccants with all my coins; 35-40% humidity.
USAF veteran 1984-2005
I keep my coins in cardboard flips, plastic air tights and other types of productive non PVC commercial products. However, I keep them in my safe in which I have a reusable desiccant canister that can be heated and turn from Pink back to Blue. I picked this up at TSC (Tractor Supply) and recharge it back to Blue from Pink and put it back in the safe till it needs to be recharged again. It's really easy and it fits great in my 40 gun safe where I keep my coins but guns aren't allowed, LOL .
USN & USAF retired 1971-1993
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Also, elevate your coins when possible. Basement/home flooding can happen from many different threats such as a burst pipe or backed up sewer line. I have a 2.5 cu ft fireproof safe bolted to steel shelving approx 4 ft off the floor and none of the coins in my fireproof gun safe are closer than 18 inches to the floor even though I have two sumps. None are under pipes (that I know of). It's all about minimizing risk. Lastly, consider insurance either as part of your homeowners/renters insurance or as a standalone policy.
Here’s some good ideas from an old book if you want to do old school “time capsules” to preserve rolls of coins or raw coins in saflips. Just put them in jars or empty paint cans with desiccant and they pretty much will remain the same as when you put them inside. You can also put special slabbed coins in these, like if you have a valuable copper slabbed coin that you want to protect, you can put a few slabs in these type of jars too.
I do that and use these type of rechargable desiccant packs like these
And I recently bought some of these jar lids that have humidity meters built into them