By Peter Mosiondz, Jr.
Many collectors do not even give it a thought. Yet every year, thousands of coins costing considerable sums are ruined due to improper storage methods.
Elementary my dear Watson! My dealer would never sell me a coin in a holder which could effectively damage the coin over a period of time. How wrong is that thinking?
Many dealers house their coins in vinyl flips made of PVC (polyvinylchloride). These holders are soft and very pliable. They are not only much easier to handle but also to get a good view of the coin’s rim. The dealer may tell you that this holder is meant only as a temporary conveyance and that you should switch the coin to a rigid, non-PVC, inert holder once you bring the coin home. The mail-order dealer or auction house will usually stamp their invoices with a warning message of this sort. Oftentimes however the collector pays no heed.
PVC will, over time, deposit a sticky, slimy green chemical plasticizer on a coin and, at the same time, emit hydrogen chloride gas if the coin is stored at an excessively high temperature. In extreme cases, this hydrochloric gas can react with atmospheric humidity and form hydrochloric acid, which can easily eat into the surface of the coin which is termed “pitting”.
These green substances and pitting are the result of a coin reposing too long in an improper holder.
PVC is much more prevalent that one might imagine. Many of the flip-type holders sold today contain this harmful substance. There is one flip though that does contain any harmful PVC. Instead, it is made of pure polyethylene terepthalate, most commonly known to us non-chemists as Mylar®. These flips carry the brand name of “Saflips” and are worth every cent of their cost.
Be extremely wary of any soft and pliable flip, especially if you are told that they are safe to use for long-term storage. I’ll bet that they’re not. Chances are that they contain some measure of PVC.
Sulfurs and other airborne contaminates are also to be avoided. Those two-by-two-inch paper envelopes that I once used as a neophyte collector, as well as any product employing the use of paper or cardboard, should be viewed with a great deal of caution’ better to ignore using them. The Mylar® two-by-two-inch holders that one staples on three sides also contain cardboard, but the section housing the coin is inert. It is very thin however and over time, if it should crack or even receives just a pinpoint hole, the coin could experience the type of damage that we just alluded to. Without the Mylar® protection, the coin becomes subservient to the cardboard.
Many times these flips or Mylar® holders are placed in a cardboard or plastic storage box coin wallet or vinyl coin pages. Again, caution is the by-word here. Each of these products contains some sort of ingredient that, by itself, could pose a danger to your coins. There are inert storage boxes available from the same firm that offers the Saflips and there are inert coin (or slide) pages that hold 20 of the two-by-two-inch holders. These pages are then inserted into a three-ring binder. Firms that sell archival supplies, such as Brodart for example, offer inert pages and binders.
I have used other types of holders over the years but nearly as much as the two types already mentioned. The key word here is “inert”. Choose nothing else. There are several types of snap-together holders, holders with glass protection that screw or snap tight. If using a snap-type holder make certain that it closes absolutely tight. If not, air will penetrate and damage to the coin could ensue.
There are several holders on the market, past and present, that I have not used therefore I can not offer any advice or suggestions. Again, remember our key word – inert.
There are other methods of storing or housing your coins. Included are coin tubes, folders and albums.
With coin tubes, even if they are certified as being inert, or free of plasticizers, one can risk the very real fact of damage by scratches or “rub” when coins come into contact with one another. Rub is essentially wear on a coin. Coins falling one upon another when inserted in a tube can easily be damaged. I would steer clear of tubes unless I was saving circulated coins out of circulation. They are always spendable.
One of the common types of folders, and one I used extensively as a youngster, is the folder that one pushes the coin into a pre-cut slot. These folders, unless inert, have a sulfur content that affects the reverse and rims of the coin. The sulfur will one day even affect the coin’s obverse. Even with inert folders the obverse is exposed to air contaminants.
Many of the coin albums on the market have acetate slides that cover the slots for the coins. Normally the rear (or bottom) slide stays in place. One moves the front (or top) slide out a bit to allow the insertion of a coin. First, use cotton gloves when pushing the coin into the slot. Secondly, remember that these slides, even if they contain no plasticizers, can cause friction damage to a coin’s “high points”, or the most elevated portion of the design. The constant moving in and out of these slides will cause scratches and rub (or wear) on the coin. If you use this type of album, be absolutely certain the neither slide will come into contact with the coin. And, be sure to inquire if the album is free of PVC and sulfur content. In other words is the album inert? Some of the newly designed albums and holders have inert neoprene rings to help prevent sulfur and other damage to the coin’s rim.
Some added and reminder precautions are in order.
- Store your coins in a cool, dry climate. I maintain a 75-degree (F), low humidity environment on my coin office. I also use silica.gel containers, each holding 360 grams of the substance. When they have their quantity of moisture, I follow the instructions and regenerate them by oven baking. If you ever wondered what causes black spots on a coin, it is moisture. Silica gel helps remove moisture from the air.
- If you use a safety deposit box at your bank or use a home safe, be sure to place a silica gel container in each one. Don’t mix coins and paper items together in the same box or safe. Get a separate fire-proof box for the important documents.
- Always ask, “Is this holder, folder or album PVC free and inert?”
- Be careful when using slide-type albums.
I will mention encapsulated holders (or “slabs” if you will) briefly. The top certification firms today do use inert containers and will back their product with a repurchase guarantee. This guarantee will reimburse the owner at the prevailing market price if the coin should sustain any damage while in the firm’s untampered with holder. Check first to make certain that the issuing firm adheres to this guarantee. The two largest firms do abide by it.
Until next time, stay well and enjoy your hobby.