Storing Coins Please help

Discussion in 'Coin Chat' started by Ryanf88, Mar 16, 2016.

  1. Ryanf88

    Ryanf88 New Member

    Hello all

    I have some coin sets and I have them in cardboard cases (as seen in pictures). They were in a lock box where none of the documents were damp or wet in there. Well some quarters started turning green on the edges. If I take it off the finish comes off so they are ruined now sadly.

    Question is: How should I store my coins, is a box with air flow better then a air tight safe or maybe have Silica Gel in there too?

    Assuming there is nothing to do but replace the coins now right?

    I also have a few bills they are not moldy or green but they smell musty, what is the best way to store those?

    Thank-you in advance everyone.

    Attached Files:

  2. Avatar

    Guest User Guest

    to hide this ad.
  3. Lon Chaney

    Lon Chaney Well-Known Member

    The silica gel is good. Are you in a high humidity area?
    That green may be a contaminant.
  4. Lon Chaney

    Lon Chaney Well-Known Member

    Oh, and welcome!
    Other members will have some more thorough responses.
  5. SuperDave

    SuperDave Free the Cartwheels!

    Your first and deadliest enemy regarding coin storage is oxygen. Humidity is bad, but virtually all adverse coin reactions are functions of oxidation, or reactions in which oxygen plays an important role. Your second enemy is keeping the coins in contact with something containing chemicals capable of reacting with them in the presence of that oxygen. In this case, it seems both conditions have been met, and you're now paying the price.

    Green is a panic-level color when it comes to coins. It's usually present when the worst of possible reactions have occurred. The flaky appearance, and the fact that it's so visible on the cardboard as well as the coins, indicates that the cardboard itself was a deadly choice on the part of the manufacturer considering what they intended to be placed there. I can't say I'm positive yet what precise chemical process ended up like this - I've rarely seen such involvement of the actual container in similar cases and the flakiness spreading onto the cardboard throws me a bit - but the solution is clear and my recommendation never varies.

    Keep your coins and bills individually packaged in archive-quality containers, and prevent oxygen from reaching them. I'm a big fan of vacuum packing. Silica dessicants are an excellent idea as well, although the same processes which keep oxygen from your valuables also tends to keep humidity out.
    tommyc03, Stevearino and Paul M. like this.
  6. Paul M.

    Paul M. Well-Known Member

    That safe does not look good for humidity issues. Lots of inexpensive safes have humidity retention issues, especially if they're the so-called "fireproof" variety.

    As for the coins, any that you want to preserve, I'd remove from the cardboard holders immediately, give them a bath in some acetone (which will probably take off the green if it's anything worrisome), and then store them properly in inert plastic holders with silica gel in the container as well. Don't rub the coins at all when you use acetone, just let the acetone evaporate.

    There are posts on this forum that go into detail on all of the points I just made. I'd suggest you search google for more info (which will probably point back here). You can add to your query if you specifically want results from here.
    Stevearino likes this.

    GDJMSP Numismatist Moderator

    Stevearino likes this.
  8. Lon Chaney

    Lon Chaney Well-Known Member

    The coins in the top pic are 1999, when quarters were still 99.9% nickel.
    Not sure about the date on the Olympic ones. The current steel coins have a tiny amount of copper, so if they're post-1999 I guess it could be verdigris.
    Paul M. likes this.
  9. Cascade

    Cascade The Blind VAMmer

    Huh, my first thought 9f coarse is verdigris but how is it jumping from the coin onto the cardboard. And it's cake-like, looks almost like plastic flecks. Think I wanna get this guys opinion @BadThad
  10. Maxfli

    Maxfli Well-Known Member

    This. Your first order of business is to get rid of that box and do not replace it with any of the similar cheap fire retardant boxes/safes sold at home centers.
  11. Ryanf88

    Ryanf88 New Member

    The Olympic ones are 2010, and the other set is 1999.
    I am not sure what the green is from and yes it is "jumping" onto the cardboard which leaves me puzzled as well. I took one of the coins I have a spare of and took the green "growth" off and it flakes off, and leaves a mark on the coin. Not sure is acetone will remove this, I will have to get some to try tomorrow.

    The cardboard holders were both from the Royal Canadian Mint so I would have thought they would be chemically safe to put a set into, but I guess they are not.

    Thank-you again for the help everyone I look forward to hearing more responses and using this site :).
  12. Stevearino

    Stevearino Supporter! Supporter

    Welcome to CT, Ryan; sorry it had to be about damage to your coins.

  13. tommyc03

    tommyc03 Senior Member

    Dave's answer was certainly very helpful. I'm almost sure that trapped moisture played the most important part here as you mentioned a musty smell on the notes but you do not see any mold. If you take a very soft white tissue and wipe across the face of one of the notes and come up with anything like gray or black then you will have mold, or even white mold. The moisture is what is causing the green with an interaction of the cardboard holders, moisture and coins. I had this happen to some Canadian sets while stored in a closet. My first sign was mold on a leather jacket although I could see none on any of the clothing next to it. It was still there though and my fault for not opening the closet from time to time to air it out. Coins stored in the "velvet " boxes will deteriorate after time also and stick to the coins if they are not encapsulated. My advice is to follows Dave's. Good luck.
    Stevearino likes this.
  14. Kentucky

    Kentucky Supporter! Supporter

    Verdigris is most often related to copper coins since it is usually considered as one of the compounds of copper. Greenish crud on other coins could be referred to as "green crud". Whatever it is, it is unwelcome. Paper touching coins is always iffy. The cheapest way to get some protection is to put the coins in 2x2 holders that have a Mylar (polyester) film that protects the coin. Hard plastic coin "snap" cases would be better, but more expensive.
    Paul M. likes this.
  15. desertgem

    desertgem MODERATOR Senior Errer Collecktor Moderator

    I do not believe it is a copper compound, the color is wrong. This is more the color of Ni(II)O, nickel oxide which makes some sense on same metal coins, but does not form as easily as copper compounds so origin is a mystery.
    Stevearino, JPeace$ and Paul M. like this.
  16. Kentucky

    Kentucky Supporter! Supporter

    Yeah, the point was made that these were pure nickel coins. I was just noting that when the phenomenon is seen on copper alloys it is called verdigris.
    Paul M. likes this.
  17. GDJMSP

    GDJMSP Numismatist Moderator

    You guys are the chemists so you know far more than me. But what I know is that verdigris, or at least what we non-chemists call verdigris, forms not only on copper coins but on silver, gold, and clad coins too. Does it form as often as it does on copper ? No, no where near that, but it does form.

    And yeah, I figured the cardboard could be playing a part in the unusual color, as well as playing a part in accelerated growth causing the "green" to spill over from the coin onto the cardboard itself.
  18. Lon Chaney

    Lon Chaney Well-Known Member

    Those are alloyed with copper though.
    Pure nickel isn't.
  19. Kentucky

    Kentucky Supporter! Supporter

    @BadThad help. I think any sort of colored decomposition on any sort of coin is widely viewed as verdigris.
  20. GDJMSP

    GDJMSP Numismatist Moderator

    And I'm not arguing that point Lon. Kentucky and Jim probably know, or have a good idea, what the green stuff really is - but I don't know what else to call it but verdigris.

    Bottom line, it's the green stuff that metal turns into when it corrodes.
    SuperDave and Kentucky like this.
  21. Kentucky

    Kentucky Supporter! Supporter

    Stevearino and Paul M. like this.
Draft saved Draft deleted

Share This Page