The Smithsonian Institution's rare coin holdings comprise the most valuable and most important collection of its kind. The National Numismatic Collection, as it is formally known, more than adequately fills it role as our nation's coin collection. It includes rare specimens presented to foreign leaders in the hopes of developing trade relations, and medals presented to native chiefs as our country grew westward. It now houses the many ancient coins that inspired President Roosevelt to commission Augustus Saint-Gaudens to redesign our coins such that they would rival the treasured coinage of ancient empires. It includes the unique 1849 Double Eagle, far-and-away the most valuable U.S. coin, which is a monument of the gold finds that heralded the prosperity that was to come to our still-young country.

The reverse of a 1794 Large Cent showing a large area of wax throughout the reverse. Click to enlarge		The same coin as to the left, now with wax removed. Click to enlarge
All Photos by David J. Camire for the Smithsonian Institution.

Even with all its innumerable treasures and tremendous monetary value, the collection now demands our attention and efforts to preserve it for future generations. Numismatic Guaranty Corporation (NGC) and Numismatic Conservation Services (NCS), with the assistance of Jeff Garrett and others, have offered services and financial support to assure that its coins are accessible through exhibit and to researchers, as well as properly stored and maintained. A necessary first step in this process is conservation.

Conservation of the Smithsonian's National Numismatic Collection to our minds represents a new evolution in our way of thinking about important coins and collections. More than ever, we recognize the role that conservation plays in our critical responsibility to see that numismatic properties are given the best opportunity to be appreciated and studied for years beyond our own. Furthermore, the experience of working with the talented Smithsonian individuals has added new precision and sophistication to the general understanding of numismatic conservation.

The process of this conservation begins by removing contaminants from a coin or metal's surface. Our goal is to perform this while preserving the original patina of the coins. The surface of any metal object will change over time, but most often it is the presence of a foreign substance that speeds and exacerbates its degradation. Once removed, the surface is then neutralized. This provides the ideal scenario for long-term stabilization and preservation.

A 1795 Flowing Hair Dollar with a small wax remnant on the upper obverse. Click to enlarge		The 1795 Dollar with wax removed. Click to enlarge

The first conservation efforts with respect to the National Numismatic Collection are focused on wax removal. Wax was used to suspend coins in exhibit, and often its remnants lingered on coins long after being displayed. As the wax is not present on the entire coin, only certain areas are affected. Portions of the coin’s surface may have responded differently to their environment as a result. No previous conservation effort has focused on removing this material. Professional conservators rely on chemical means for its removal, but most numismatists and outside researchers are unaware of the proper procedures. NCS and the Smithsonian conservators' methods guarantee the safe removal of wax.

A second part of the conservation process is to remove dirt and grime that happened upon the coin as a result of open storage, either while on exhibit or in the Smithsonian's vaults. Much of the collection is housed in cabinets on open trays, which makes the coins vulnerable to dust and environmental threats. Again, removal is best accomplished through a chemical aqueous procedure rather than mechanical means.

The final stage of our preliminary efforts is to develop a long-term storage solution. NGC has conducted considerable research on its own holders and, after eighteen years of operation, has determined the best plastics and seal types to achieve this goal. While research is still ongoing with the Smithsonian, a re-closeable holder will be adopted for their use. Such a holder will improve the ease of handling and adds an additional level of protection.

I look at the work that has begun at the Smithsonian as among the most important in my career. I believe that new exhibits and novel ways of sharing this unique resource will certainly broaden our hobby's appeal. Moreover, the breadth of the National Numismatic Collection enables a researcher to travel down every avenue in numismatics. With proper conservation and preservation, this can continue into the future.

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BEFORE Click to enlarge

AFTER Click to enlarge

Mints around the world produced specially-made pattern coins to show proposed coinage designs and concepts. This Decimal One Penny coin of Great Britain was produced to show both. This Penny depicts the beautiful Una and Her Lion design first used on the British Gold 5 Sovereign of 1839. The denomination demonstrated a new concept in British coinage that would finally be adopted more than 100 years later — decimal coinage. Thick residues were obscuring the bright copper surfaces beneath. If left alone, these residues could damage the surfaces irreversibly. Using professional conservation techniques, NCS conservators were able to remove the residue carefully, revealing the brilliant coin we see today.

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Among the rare and popular early 1795 silver dollars are those with a peculiar plug of silver in their centers. It is theorized that some underweight silver dollar planchets were plugged with additional silver to bring up their silver content. This 1795 silver dollar exhibits the faint outline of a silver plug in the center of both the obverse and the reverse. This particular example has also been given the Variety Plus treatment offered by NCS and has been attributed according to the Bowers-Brockhardt reference on Early Dollars. This service is available for an extra fee. For information on the specific varieties that can be attributed, please see the NCS web site at www.NCScoin.com.

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NCS will be on-site at PNG Day and the Central States Convention in Columbus, OH April 26-29. NCS show representatives will be available to accept submissions and offer opinions. NCS will be at tables 10 & 11.

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The Collectors' Society Message Boards include an Ask NCS forum. Members are invited to post questions which are then answered by NCS conservators. A broad range of topics are covered, from NCS procedures to specific conservation questions. The forum is available for browsing, and your inquiries are always welcome: ASK NCS.

Following are some recently posted questions which may help to answer some of your questions about professional numismatic conservation:

I've got some 1943 steel cent which looked new when I got them, and have since rusted. What can I do?
Rust or corrosion is a problem with coins having high iron content, such as the 1943 steel cents. The zinc coating helps reduce the rate of corrosion. If corrosion appears quickly, it is possible that the coins you mention have been reprocessed. Reprocessed steel cents are circulated or corroded pieces that have been replated with zinc in an attempt to make them appear uncirculated.

Regardless of how your coins became corroded, there are steps that can be taken to reduce the damage. First, store your coins in a cool, dry place. Use airtight holders that are free of contaminating residues such as PVC. The two simple measures will help reduce the amount of corrosion on any coin, not just steel cents.

Can NCS remove "milk spots" from Peace Dollars?
What are commonly referred to as "milk spots" on Peace Dollars usually cannot be removed by conservation. These spots were created during the manufacture of the coin at the planchet stage. The substance causing these spots is embedded in the metal of the coin, and removing them can cause irreversible damage to the surfaces of the coin.

I have a copper cent with a very distracting fingerprint etched on the obverse. There is also a big carbon spot on the obverse which I would like to have either removed or toned down. Can NCS help out in this?
Fingerprints can become etched into the surface. When this occurs, there is seldom much that professional conservation can do to help the coin. We are not able to restore the coin's surfaces. What are commonly referred to as carbon spots can be caused by a number of things, some of which can be helped with conservation while others are deep in the planchet and would result in damage if removed.

I rather like odd and dark toning that some find unappealing. If I want the coin to go through conservation processes only if NCS believes the surfaces of the coin would result in a rejection from NGC, but I don't want it to be touched if it is likely that there won't be a rejection, is that an option on the submission form? Or will the conservers say "Oh, this is a coin that can be improved even though it would probably pass for grading" and go to work on my precious (but arguably ugly) toning?
There is a section on the current NCS Submission Form to add notes about the conservation of your specific coins. Your concern about the toning is exactly what this section is for. The notes are considered through the evaluation and conservation process. More often than not, if a coin will result in a no grade due to the surfaces under toning, that toning will not be removed, and the coin will not be conserved.

Can NCS representatives attending a coin show evaluate a coin and advise me whether conservation can help?
NCS representatives do attend shows. Depending on the show, we may have a representative who can look at your coin and give a quick informal opinion. Occasionally, when coins arrive in our office, we discover that a coin should not be conserved during formal evaluation. In such cases, the NCS evaluation fee is NOT waived. Contact NCS Customer Service at ncshelp@ncscoin.com or 866-627-2646 to find out if someone will be able to do this at the show you plan to attend.

I had picked up some particularly well struck Washington quarters in 1989 while traveling and wrapped them in tissue till I returned home. Well, I forgot them and the years went by and they have some spectacular toning now. So the question is, have they been artificially toned?
The determining factor for "artificial toning" is not as much the method of acquiring color as the appearance of the color itself. No one but you can say for certain how the color formed, but an expert can judge the toning. Experience is the best way to determine artificial color.

The appearance of the color will determine whether a coin has artificial or natural toning. Unusual color combinations as well as bright colors are frequent signs of artificial toning. A smoky or opaque appearance of the color is also often a sign of artificial color as is color that completely hides defects, such as contact marks or hairlines. These are just a couple of the clues to look for when trying to determine artificial color.

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I just picked up this great Morgan dollar, but it has a bit of grease on Liberty's nose. What are the odds that you guys would be able to get it out?
From the appearance of your image, we would guess that the spot on the obverse of your coin is struck in the planchet. If that is the case, we likely would not be able to help it much. The streak may be lightened, but would remain. If it is not in the planchet, then we likely could remove it.

I have a $3 gold coin with 3 small spots of glue residue on the reverse. Is that something NCS can remove and then holder in an NGC holder?
Glue residues are typically something NCS could remove from the surface of coins. Typically glue residue does not cause any damage that would cause a coin to "no grade" with NGC. We have seen situations when glue residue was hiding a spot removal or hairlines. This is, however, the rare exception. If a coin would "no grade" after the conservation of glue residue, it would likely be for a problem other than that residue.

I have acquired a nice 1916/16 DDO Buffalo in G4, except for a bit of dark green "corrosion" spots on the obverse. I do not think it is PVC residue, and with this coin being what it is, I do not want to attempt spot removal myself and risk damage to the surface. Is it a candidate for conservation, and possible grading by NGC?
Our goal in conserving any coin is to help it grade with NGC. Occasionally, a coin has irreversible surface detriments, and grading with NGC is not possible. When a coin has an irreversible surface condition, such as improper cleaning or environmental damage, our goal is to conserve the coin by removing residues and/or undesirable toning in an attempt to make the coin stable for long-term storage and more attractive to the eye.

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