Safely storing copper and bronze coins

[Paul H]

Hi all

I'm very frustrated to see that a number of copper / bronze coins which I stored in plastic coins envelopes, within a wooden box, have developed green verdigris or similar round the edges, and also feel 'sticky' on the obverse & reverse. I'm sure that the envelopes claimed to be 'coin safe' but they were from EBAY a few years ago. Would a move to more expensive plastic coin envelopes or albums prevent this in future, or is all plastic a bad idea for copper and bronze? Any suggestions for safe storage welcome (I'm aware the Lindner type coin trays would be better but these are quite low value coins, probably not worth buying multiple new trays for). 

And is there a safe way to remove the mild verdigris / stickyness?!

Apologies if this has come up before, and thanks in advance for any advice, Paul 

[PWA 1967]

Paper coin envelopes are the best, although you cant see the coin unless you take it out, i doubt you spend hours gazing at them ?.

You can just write on the envelope whats in it and easy to store as dont take any room up.

Thats unless you want to buy a cabinet 😃

As far as removing any plastic thats leaked through the coins being on top of each other (they are better stored vertically) its better left unless there is any value and if so removed by someone who knows what they are doing.

[Sword]

Never store coins in PVC containing envelopes as the plastic will release chemicals harmful to coins and cause the problem you have. You need to use envelopes made from an inert material like mylar. 2x2 coin flip is also an option and has the advantage of being airtight. I would only buy branded products (or at least from an established supplier), and I wouldn't take the word of a seller on eBay that their envelopes are "coin safe".

If using paper, then it should be acid-free.

[jelida]

1 hour ago, Paul H said:

Hi 

And is there a safe way to remove the mild verdigris / stickyness?

Pure Acetone is your friend here, just bathe the coin for a few minutes and dab gently with good quality cotton wool, or brush with a very soft brush while still immersed. Practice on lesser coins first,  and beware that acetone is highly flammable and volatile. Available on EBay and most chemists.

Jerry

[Paddy]

Acetone is very expensive from chemists! Try Ebay/Amazon or some hardware stores.

Don't use the Nail Polish remover, which is Acetone based but has other chemicals added.

 

[copper123]

You can get the good stuff off ebay even if it is never supposed to be posted 

I bought a 2 ltr bottle a few years ago and still have loads

[Paul H]

Thank you all for the comments so far. I think I have some acetone in the shed - will try that carefully!

[Sword]

Good luck. The experience gained could be useful if you ever need to do it for a higher value coin one day.