U.S. & World Coin News and Articles

Coin Preservation

Some people acquire rare coins primarily for pleasure, others primarily for profit. Some regard themselves first and foremost as collectors, others first and foremost as investors.

However you view yourself and your coins, you'll never achieve your objectives unless you take care of those coins -- for protection and preservation are the common allies of collectors and investors alike, and deterioration and damage are the common enemies.

In 1985, a collector client came to me with a group of coins that once had been -- and still should have been -- truly incredible. The group contained a Liberty Seated half dollar with spectacular cameo contrast and beautiful toning ... several highly desirable and scarce-date Indian cents, including an 1864-L, an 1877 and a 1908-S ... and a high- grade, scarce-date Barber dime.

All of the coins were well preserved -- or at least the client thought they were, since all had been stored in nice, soft vinyl flips. The trouble was, those flips were made of PVC -- polyvinyl chloride -- and the coins had all corroded while in storage.

The moral of the story is that a coin holder costing just a couple of cents can easily ruin coins costing many thousands of dollars.

Coin storage problems are a matter of utmost concern. Whether you buy coins to hold for long-term gain or to sell in a nearer term when the time is opportune, you stand to lose a great deal of money if those coins deteriorate while in your possession.

The preservation risk is a clear one. If you buy a coin for $1,000 and drop it on the way home and the coin gets a scratch on it, that $1,000 coin can plummet in value to $100 -- even if you got good value in the first place -- because of the loss of condition.

Many collectors and investors have experienced similar losses in the value of their coins -- not because they dropped them, but because they stored them in unsafe holders or unsafe environments. Yet, in many instances, they haven't sought or received advice on how to avoid recurrences. Clearly, there is a lack of appreciation for the seriousness of the problems and a lack of education on how to combat them.

Coin preservation is a never-ending struggle. Coins begin to deteriorate the second they are produced. Every coin you see -- even the highest-grade mint-state coin -- is in an intermediate stage between having been completely brilliant and turning completely black.

Coins are affected by a multiplicity of variables. Bern Nagengast, a well-known authority on coin preservation who is the principal of E&T Cointainer Company in Sidney, Ohio, says the rate of a coin's deterioration depends primarily on the metal of which it is made, the atmosphere, the contaminants on the coin's surface and the handling of the coin.

As the owner of a given coin, you can exercise control over a good number of these factors and thereby slow down -- and perhaps all but stop -- the deterioration of your coins and keep them in the same level of preservation over the years. You owe it to future generations of collectors to do so -- to maintain your coins in the same level of preservation when you store them. And if moral and philosophical considerations aren't persuasive enough, you owe it to yourself--because if you don't, you stand to lose a whole lot of money.

Let's consider the most important factors affecting a coin's long-term life.

The atmosphere surrounding a coin certainly can have a significant effect on how well, or how poorly, that coin holds up.

According to Bern Nagengast, normal pollutants found in the air can cause serious long-term problems by combining with oxygen to damage a coin's surface. Artificial gases produced while a coin is housed in a plastic holder, coming from the plastic itself, also can cause major damage.

The atmosphere contains moisture and dust, and both are dangerous to a coin, for both carry oxygen into intimate contact with the surface of that coin.

Since we don't have much control over the air around us, the best way to protect a coin from the atmosphere is to place it in a container that's as airtight and inert as possible. That way, impurities in the air will be kept away and, at the same time, the container itself won't contaminate the coin.

The problem is, no coin holder yet devised is absolutely airtight. Even coins that have been encapsulated in sonically sealed, tamper-resistant holders by the major grading services are not 100 percent impervious. These holders are somewhat airtight, and the plastic of which they're made is chemically inert -- but they're not completely airtight, and air does come in contact with the coins inside, though admittedly at a greatly inhibited rate.

This is not to minimize the importance of safe and effective holders. On the contrary, they can play an invaluable role in safeguarding your coins.

Susan Maltby, a well-known preservation expert from Toronto, recommends holders made of either Mylar, polyethylene or polypropylene. All three are tough, stable compounds -- and unlike PVC, they won't break down readily into their chemical components.

As for PVC, Sue Maltby has a three-word recommendation: "No, no, no!" PVC "flips" gained wide popularity during the coin market's boom years of the mid- and late 1970s because they are exceptionally clear and flexible. This seemed to make them an ideal way to store and display rare coins. In time, it became apparent that these relatively minor conveniences came at a very high cost -- for when heat and light act upon PVC, it breaks down chemically and hydrochloric acid is released. This, in turn, can cause chemical damage to the surface of the coins that the holders are supposed to be protecting.

Often, plasticizers are used to enhance the chemical properties of PVC holders, and these can ooze out and form an oily film upon the coins, greasing the skids for still further damage.

The perils of PVC were publicized extensively in the early 1980s, and since then there has been a noticeable decline in the use of such holders. Obviously, though, not everyone has gotten the message: Recently, the Numismatic Guaranty Corporation of America (NGC) issued a press release reporting that it has received a substantial number of coins with PVC damage.

Those coins were submitted to NGC by dealers, collectors and investors seeking to have them certified and encapsulated by the company, which is one of the nation's leading coin- grading services. Instead, they got their coins back uncertified, since NGC and other grading services make it a policy not to grade damaged coins.

Mark Salzberg, NGC's president, suggests that many of the damaged coins now entering the marketplace may have been set aside years ago, before the risks of PVC were fully understood.

"Collectors and investors should check any coins they have put away -- in safe deposit boxes, for example -- to make sure the holders are chemically inert and the coins have not been damaged while in storage," Salzberg said.

Those who suspect that their coins may have been exposed to PVC should remove them from their holders immediately, he said, and take or mail them to a dealer familiar with how to neutralize the chemical and, if possible, remedy any damage.

"We're alerting NGC-authorized dealers to the problem and advising them what can be done to deal with it," he said.

Of course, PVC isn't the only source of potential damage to your rare coins. Other caustic chemicals, such as compounds containing sulfur, can harm them, too. Even you yourself could be the source of damage: If you chanced to touch a coin with a perspiration-soaked thumb, for example, that coin could end up with a thumbprint permanently etched in its surface.

This, by the way, is another illustration of why "slabbing" won't necessarily guarantee the permanent safety of your coins. If your sweat-soaked thumb came in contact with a coin and the coin was then certified and encapsulated, the chemical damage caused by that contact could continue to develop even within the sonic seal of the "slab." It might take longer for the etching of that thumbprint to appear, but eventually it would rear its ugly whorls.

Frequently, coins carry the seeds of their own destruction -- without any help from the atmosphere or other external factors.

Bern Nagengast and Susan Maltby share the view that however pristine they may look, coins are essentially dirty. During production, the metal used in coins is rolled, punched, annealed, die-struck and handled by various mechanical devices. Even proof coins are contaminated with metallic particles, and even the most meticulously preserved business-strike coins suffer from a multiplicity of contaminants: oil and grease ... rag dust ... bag dust -- you name it, they've been exposed to it.

After the coins leave the Mint, they're further contaminated by counting machines and handling. Even when you simply hold a coin, you're contaminating it -- and sometimes, the contamination can be devastating. If you eat a pastrami sandwich over your proof Trade dollar, you're contaminating it. If you have dandruff, you can contaminate it. If you eat chicken wings and then touch a coin, you can permanently ruin its level of preservation. If you talk over a coin, the saliva from your mouth can land on the coin and turn that area black -- and then actually penetrate the surface of the coin.

How you hold a coin can be important, too. If you don't hold it properly by its edges and the mishandling causes abrasions, you can ruin the coin. Likewise, a coin can be damaged by coming into contact with other coins or rubbing against some other foreign substance -- even a velvet cloth.

Another crucial aspect of coin preservation is coins' metallic makeup. Some coins are more prone than others to chemical and environmental damage; some, by contrast, are more resistant.

Gold retains its mint luster almost indefinitely -- although, as Sue Maltby notes, that depends on how pure the gold is. Some gold coins contain copper -- and in such cases, the copper might cause them to break out in spots.

Silver is quite resistant to corrosion, but it's highly susceptible to tarnish, especially in the presence of sulfur compounds and nitrates. And Bern Nagengast points out that sulfur and nitrate compounds are frequent components of air pollution today, so these are real concerns.

Copper coins are especially susceptible to damage from airborne particulate matter, and can break out in spots virtually without notice. For this reason, you should take special pains not to store copper coins in a moist environment.

According to Susan Maltby, vulnerable metal coins will start to corrode when the relative humidity in the surrounding air rises above 35 percent. Obviously, then, the risk of corrosion is higher in a damp, humid place such as Florida than it is in a drier climate -- the kind found in Arizona, for example.

To combat this risk, you need to create what Sue Maltby calls a proper "micro-climate" -- a neutral, acid-free climate -- for your coins.

One way to accomplish this is to treat the air surrounding the coins -- the air in your safe-deposit box, for example -- with a vapor-phase inhibitor. This is a substance that changes the molecular composition of the air to retard the process of tarnishing.

Sue Maltby reports that museums have used such products for many years. She cautions, however, that vapor-phase inhibitors tend to be specific for certain metals; in other words, a "VPI" meant for use with silver might be of little value in retarding damage to gold or copper coins.

Silica gel also can be beneficial, she reports. If you've purchased a new camera or radio lately, you've probably noticed a small packet of silica gel in the box.

Silica gel and silica are "very handy for maintaining a dry environment," Maltby says. Basically, they serve as sponges, drawing all the moisture out of the air.

Sue Maltby also recommends dipping your coins in a neutral solution, such as alcohol, before storing them. For his part, Bern Nagengast advises that you treat them with an evaporative freon solution such as trichlorotrifluoroethane.

This protects the surfaces of your coins from environmental damage, yet is harmless itself to the coins.

Obviously, proper preservation is a lot more complex than simply sticking your coins in plastic holders, tossing those holders in your safe-deposit box, then walking away.

As with any other aspect of coin collecting, though ...

or any other aspect of life in general ... the more you put in, the more you get out.

And if you don't expend enough time and effort protecting and preserving your coins, what you get out of your safe-deposit box may prove to be a whole lot less than what you put in.

Scott A. Travers ranks as one of the most influencial coin dealers in the world. His name is familiar to readers everywhere as the author of six bestselling books on coins: The Coin Collector's Survival Manual, The Insider's Guide to U.S. Coin Values (annual price guide), One-Minute Coin Expert, Travers' Rare Coin Investment Strategy, The Investor's Guide to Coin Trading and How to Make Money in Coins Right Now. Mr. Travers appears frequently on television and radio and has served as COINage magazine contributing editor since 1984. He invites Coin Universe visitors to read free excerpts from some of his books.

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