Preparing Coins for Storage

Discussion in 'Coin Chat' started by charlienorth, Dec 19, 2009.

  1. charlienorth

    charlienorth Junior Member

    I noticed dust, or whatever, on this coin in a hard plastic holder.

    [​IMG]

    This reminded me that I want to put quite a few coins in new holders.

    I've read here and in books that most chemicals, including acetone, harm the coins finish.

    I thinking of dipping the coins in denatured alchohol to remove potential oils/minor contaminations and placing them on a cotton cloth to dry before placing them in a holder.

    On the holders, (mainly 2x2s but some airtites) I plan to use feather duster to rid them of dust before placing the coins in them. The 2x2s will then be taped.

    Is that about as good an approach as there is?

    And what about something like this:

    [​IMG]

    Do I just holder it as is?

    Thanks
     
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  3. GDJMSP

    GDJMSP Numismatist Moderator

    All of this has been discussed many times, but it always comes back up and so needs to be dicussed again from time to time.

    You will undoubtably hear several people who advocate dipping all coins in acetone to prepare them for storage. As you mention it is done to remove any oils from handling and light surface contaminants, like that dust you mention.

    Personally, I do not agree with this line of thinking. There are certain risks involved with even acetone. It's purity could come into question for one. And contaminants in the acetone could remain on the coin and later damage it. Handling during the process is another risk. And certain metals, particularly copper, can sometimes react with acetone and cause color changes. So I only advocate using acetone when it needs to be used instead of using it indiscriminantly. Same things can be said of denatured alcohol.

    Regarding the dust on the coin you pictured - sometimes it is just that, dust. And dust can be removed with air, thus removing any need to touch the coin with anything. Using that feather duster you mention - bad idea. It can and will cause hairlines on the coin. You do not want to touch the coin with anything, regardless of how soft you think it is. Use air, plain air and no damage will occur.

    Canned air is one method, but that too has some risk. The propellants (chemicals) in the canned air can sometimes get on the coin. But with care it can be used safely. But the risk is always there for if you tilt the can even slightly some liquid may escape and get on the coin.

    Perhaps better and safer is a new bulb squeeze, often used to remove mucus from babies' mouths and noses. A sharp squeeze causes a jet of air to blow the fine dust particles away with no harm to the coin. But you want to make sure it is a new one.

    Never blow on a coin with your mouth. Fine particles of saliva that you can't even see will get on the coin and later cause spots. You should even avoid talking over your coins for the same reason. And of course coughing and sneezing around them - big no-no.

    For similar reasons, 2x2s are a bad idea. The paper, even if sulphur free, still deteroirates and creates cardboard/paper dust. This dust will scratch coins as they move ever so slightly inside the 2x2.

    Any coin worth having in your collection is worth the cost of a quality holder for it. Air-Tites are among the best and the cheapest, 40 cents each or less for any of them.

    Something else to always remember, those little white specks you see sometimes see on coins are not always dust particles just sitting on the coin. Often they are struck right into the metal as the coin is made. And by the time you get the coin and see it - the dust particle is no longer even there. But the tiny flaw caused by it is, and it will be forever.

    Regarding the second coin you pictured - what you see on it is one of two things and maybe both, PVC residue and/or verdigris. Acetone will remove any PVC residue - one of the times when acetone is actually needed and should be used to protect the coin from additional damage. And a product called Verdigone will remove most if not all of the verdigris. Both products can cause color changes to the coin, so that must be considered. But leaving it there is the last thing you want to do.

    Now the inventor of Verdigone is a member of this forum and I will let him provide instructions for its use. But the correct proceedure for acetone is simple enough, but it needs to be followed and no shortcuts taken.

    Always use acetone in a well ventilated area. You need 4 shallow bowls. Three have a small amount of pure acetone in them, just enough to cover the coin. The first dip should always be the longest. Length of time may vary from 10 minutes to overnight depending on the severity of the contamination.

    Once that is completed, dispose of the acetone from the first bowl, never re-use it. In fact always dispose of the acetone once it is used, never re-use any of it. And do not just pour it down the sink for it can dissolve some types of drain lines. Put it a metal can and take it to a hazardous materials disposal site.

    The second dip should be at least a minute or so. The 3rd dip can follow right after and a few seconds is enough. The 4th dip should be in distilled water, again for a few seconds.

    After than, have a soft cloth on the counter or table and stand the coin on edge, and carefully lean it up against something like the counter backsplash. Let it air dry. I know many advocate blotting the coin dry with a soft towel, but that to me is too risky. Too easy to hairline the coin, especially a Proof. It won't take long for it to air dry and there is no risk that way.

    Once finished, then place the coin a proper holder and you're done.
     
  4. fagaly

    fagaly Junior Member

    solvents

    There are a number of organic solvents that can be used to remove surface contamination. Alcohols (methanol, ethanol, isoproponal, ...), ketones (acetone), etc. They have the advantage of not interacting with metals over reasonable time periods. This also assumes that the solvents are pure.

    They can not be used to remove toning, which is due to oxidation (CuO, AgO, rust if iron), sulfurization (if I can "coin" a term), some other chemical process which forms a chemical bond, or metal vapor deposition.

    Back to solvents, you should use a pure solvent. Most isoproponal (rubbing alcohol) contains 10-30% water. 100% pure ethanol will slowly absorb water from the atmosphere until it achieves a 95.5% ethanol/4.5% water equilibrium concentration. Obviously, using 100 proof vodka (50% ethanol/50% water) is not recommended, although, if you screw up the coin cleaning, you can drink what you didn't use to drown your sorrows.
    When preparing surfaces for gold plating (scientific instrumentation, not racketeer nickels), I would put the metal in an ultrasonic cleaner filled with acetone, repeat the process with pure ethanol and then air dry by blowing nitrogen gas on it. Putting the sample in a dry box containing a desiccant also works.

    If you coin is really grungy from surface, replace your solvent. Otherwise you just move crud from one part of the coin to another.
     
  5. charlienorth

    charlienorth Junior Member

    So how do you suggest removing finger prints, spittle, etc?

    Umm, the feather duster was for the mylar 2x2s. :)

    Thanks for the bulb tip! Great Idea!

    I do like the Air-tites and have a maybe 50 but I have many hundreds more of coins in 2x2s. I suppose I could see the bank for a loan. :)


    So how do we determine which it is?

    I think it looks like corrosion. Corrosion=verdigris, right?

    Great idea propping coins on their edge! I never thought of that!

    Thanks for the tips!
     
  6. charlienorth

    charlienorth Junior Member

    lol, I don't need an excuse to drink! :)

    I don't see why rubbing alchohol or the ethanol in equilibrium would be a problem?

    A dip in distilled water is fairly universally accepted as safe for a coin I believe. How would the water in the alchohols be a problem?
     
  7. GDJMSP

    GDJMSP Numismatist Moderator

    Unless you use a commercial coin dip (an acid) you can't remove them.



    Using quality holders is a philosophy, one needs to make it a habit. Buy them as you buy the coins and you'll never miss the additional 40 cents each. Don't do it that way and have to buy hundreds at a time - and yeah, it will be expensive.

    But is it really ? How much value do you think a coin loses if it becomes hairlined or scratched because you could not afford quality holders ?

    When viewed from that perspective - the holders are cheaper by far.




    Honestly, I think it is a bit of both.
     
  8. fagaly

    fagaly Junior Member

    water in solvents

    Most likely water s part of an organic solvent shouldn't be a problem as long as you (carefully) dry it off after cleaning. By the way, ultrapure water is a corrosive solvent.

    The best way to test a solvent is to use it on a new (circulating) coin, or if you want to see what it does to silver, get a 1964 quarter or half dollar close to the condition of the coin you want to clean.
     
  9. charlienorth

    charlienorth Junior Member


    My concern is saliva/fingerprints/whatever before they can be seen.

    How do you prepare/clean coins before putting them in the holder?

    Thank you again.
     
  10. fagaly

    fagaly Junior Member

    prep for holder (and I don't mean the AG)

    I'm not a ultra-purist. In case I've accidently gotten my paws on the coin, I'll use acetone (isopropanol if I don't have any acetone). If it is a really valuable coin, and I have pure ethanol, I'll do a final wash with that (saving the vodka for an internal wash;)).

    Blot (not rub) with a lint free cloth and carefully slide it into the holder. I bought a 100-pack of cloth gloves but don't use them as often as I should.
     
  11. charlienorth

    charlienorth Junior Member


    Ok, you've convinced me!

    BTW, where do you buy Air-Tites for forty cents?
     
  12. charlienorth

    charlienorth Junior Member

    Thanks for your thoughts.

    I think I'm going with isopropanol and the air dry the coin on it's edge technique as the best plan to prevent unseen contamination making it into the holder.
     
  13. Duke Kavanaugh

    Duke Kavanaugh The Big Coin Hunter

    I dont think you get them for 40 cents unless you do purchase them in bulk :D
     
  14. GDJMSP

    GDJMSP Numismatist Moderator

    You're right, they have gone up in the past couple of years. Single holders now cost 47 cents each - JP's Corner

    Even if it were a dollar each - for what you get, it's worth every cent ;)
     
  15. GDJMSP

    GDJMSP Numismatist Moderator

    Unless you get lucky enough to attempt removal when the whatever is fresh, meaning no more than a day or two old, you're wasting your time to attempt removal as it will not come off with anything less a commercial coin dip.

    Personally I don't and never have. The most I have ever done was to remove dust with air as I have described. And that only a very few times on coins bought direct from the mint in almost 50 years of collecting.

    Now you're probably gonna ask why not ? It's simple, I only bought coins that didn't need any preparation for storage. I only bought coins that I was completely happy with just as they were.

    To me, that is the real secret of coin collecting. If you have even the slightest inkling that a coin you are considering buying needs any improvement - then don't buy it.
     
  16. charlienorth

    charlienorth Junior Member


    Thanks for the link!

    Wizard gets 62 cents minimum and Brent-Krueger 71 cents.

    That's a huge savings!
     
  17. GDJMSP

    GDJMSP Numismatist Moderator

    Sign of the times I guess. When I first started buying from JP's they under 30 cents each.
     
  18. zekeguzz

    zekeguzz lmc freak

    I'm sure you are sick of me saying what I do to preserve coins, proof sets,etc. The drawback with my method is that you cannot admire and look closely due to the polypropelene not being very clear. However I think this will keep them pristine for many years with no worries. Vacuum seal them. It's fun doing it but after that ------???
     
  19. chip

    chip Novice collector

    air drying is important, I tried various materials on some low end coins to wipe them, I could find none that did not leave some traces of their use, the good news is that in winter the indoors air is much drier and air drying goes much quicker.

    some of the things i tried, qtips, cotton balls, silk, denim, nylon, plastic sandwich bag, funny how something as hard as metal can be marked by things so soft. Maybe they should make coins out of diamonds.
     
  20. Collect89

    Collect89 Coin Collector

    I was thinking coins should be made from a nice tool steel like Vanadis 10 or D2. We could then coat the cents with DLC (diamond like carbon) black color. The nickels and quarters could be coated with WCC (Tungsten Carbide Carbon) gray color. Of course, the golden dollars could be coated with TiN (Titanium Nitride) gold color. You might get 500 circulating years out of each coin.

    Only kidding of course.

    Very best regards,
    collect89
     
  21. Info Sponge

    Info Sponge Junior Member

    There's a fascinating idea. Do any of the processes for making synthetic diamonds give you enough control of the shape that you could make something that looked like a coin? It would be too brittle to circulate, it might not count as a coin in everyone's mind given that it wasn't stamped, but wow, what a collector's item.
     
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