If I store my coins in PVC free folders that also have 2x2 flips inside can bronze disease still spread between coins? For instance I think two of my coins have it and if they are stored in the same folders can it spread to others?
I don't think so. If you live in a very humid environment the chlorine ions already present on your coins (if there are any) can become active.
On this same topic, can non-PVC flips protect a coin from harmful elements near the coin? e.g.1 coin in a flip with non-acid-free paper used for attribution on the other side of the flip. e.g.2 coin in a flip stored in a desk that is made with who-knows-what
They are not air tight, but I am sure the protect coins to a degree. If your coins in flips develop bronze disease, it is likely they already contained the chlorine and just needed additional moisture to set it off. Get some Verdicare and treat the coins you are suspicious of. If the green in powdery and flakes off easily, then it is cause for concern. If it is totally hard, then you are ok.
I am glad that there is NO gold disease Mine are all in saflips/ balance of collection are in slabs. The slab holders probably offer the best protection for bronze/silver coinage to prevent toning/oxidation. Even the US Double Eagles 1857-S examples, salvaged from the SS Central America shipwreck came out perfect. These were in saltwater since 1861!
I've had bright coppers in Saflips, stored in Whitman Plastic 2x2 boxes for 20 to 30 years. I can see no degradation of the red. There are some coppers bought with verdigris in the same box in there own Saflips. To be safe, I wouldn't store them somewhere damp like the basement or garage. When I first started collecting in 1986, the proprietor of a coin shop that I frequented, showed me a US 2 cent piece in some sort of plexiglass holder. He said that he bought it red, but when I saw it, it was now completely brown. He said that he would never again buy red copper. So I was aware that I needed to be careful with red copper. I stay away from those paper 2x2 boxes, right or wrong. I have sometimes seen bright silver tone from the paper inserts if the papers extend near the exit of their compartment. If they tone it is near the upper edge where the 2 pocket openings meet. So now I started to seal the paper compartment on my new red coppers, just to be safe. But I don't seal the coin compartment. I'm not going back to retrofit my old coppers. They have withstood the test of time. I recently placed a coin with some verdigris patches in distilled water, in a glass container to treat it. It's probably been in the water for a couple or three weeks now. I check it occasionally. It seems to be working. The light patches have cleared up, but the heavier ones are still there. I'll give it more time, and generate a post if it comes out well.
I have two coins that arrived with a bit of powdery surface. Should those be quarantined even after a Verdicare treatment or are they safe in the album with the others?
No If you have PVC free flips ( mylar or such), put the coin in there and the paper in the other side of flip. For my long term coins, I heat seal the coin side. I use an older one of different company , 6 inch size , less expensive, but still on same heat wire, even though they sent spares, Do the seal right and they are waterproof also if you are in flood areas. https://www.amazon.com/Bag-N-Seal-I...coding=UTF8&psc=1&refRID=XB2NHGQDTFD5J85FFFCC
Out of curiosity, can the acid in the paper really cause damage to a coin? Especially when it is in the other side of the flip and not in direct contact with it?
I do use acid free paper for my flips, I was just curious. I know that it used to be common to keep coins in cabinets with a label under them, as you see coins with the labels still attached. I wondered if the acid or paper content might be responsible for some of the toning you see in coins from older collections, or something more nefarious.
I’ve quarantined the two culprits for now. Going to attempt the distilled water process laid out by Wayne Sayles. Soak and change the water often. After about 30 days I’ll bake them and seal with RenWax. Luckily they’re pretty cheap coins so it’s a learning experience at least. I still want to save them though.