NCS Conservation: Discoloration, Residue and Fingerprints Eradicated

Numismatic Conservation Services™ (NCS®) uses a variety of proprietary techniques to remove harmful contaminants, stabilize and protect a coin's surfaces and, in many cases, improve a coin's eye appeal. After coins are conserved by NCS, they are seamlessly transferred to Numismatic Guaranty Company™ (NGC®), an independent affiliate of NCS, for grading and encapsulation.

Below are a few highlights of coins that were recently conserved by NCS and graded by NGC.

Coins made of nickel can create some specific challenges for successful conservation. This pattern nickel 1868 5 cent coin attributed to Judd-633 was recently submitted for NCS conservation to address a dull brown color and fingerprints obscuring the obverse. The conservators at NCS have developed some specific techniques to handle the dull yellow-brown color that frequently afflicts nickel coins.

However, while the color is fairly straight forward to remove, fingerprints can be less so. The skin oils that make up a fingerprint can sometimes cause corrosion of the surface metal and are, therefore, permanent, while other fingerprints are simply residues that can be professionally removed. The fingerprints on the obverse of this important pattern coin were able to be mostly eradicated leaving only a few scant remnants of permanent impairment. Following professional conservation, this coin was able to grade numerically with NGC.

1868 5 Cent Judd-633 Before conservation Click images to enlarge.

1868 5 Cent Judd-633 After conservation Click images to enlarge.

Residues can not only be harmful if left on the surface of a coin, but also many times can have a terribly negative impact on the aesthetic value of a coin. This 1879-CC Morgan silver Dollar was recently submitted to NCS with a dreadful heavy reddish-brown residue covering much of the high points on both sides. When residues are this extensive the potential for damage to the surface underneath is a concern. The professional conservators at NCS were able to successfully remove the obscuring residue from this Morgan Dollar and luckily, little permanent damage was left by the residue. After successful conservation, this coin was able to grade well with NGC.

1879-CC Morgan Silver Dollar Before conservation Click images to enlarge.

1879-CC Morgan Silver Dollar After conservation Click images to enlarge.

A poor choice in coin holder can lead to unattractive and dangerous residues. Case in point is this 1946 Booker T. Washington silver Half Dollar that had developed an advanced PVC residue due to long-term storage in an inferior coin holder containing PVC. Not only are PVC residues unattractive but can frequently lead to the corrosion of underlying surface metal which is irreversible. The conservators at NCS are quite skilled at removing PVC residues and upon the removal on this commemorative Half Dollar little permanent affects remain. Following professional conservation, this modern mint error coin was able to grade well with NGC.

1946 Booker T. Washington Half Dollar Before conservation Click images to enlarge.

1946 Booker T. Washington Half Dollar After conservation Click images to enlarge.

For more information about NCS, visit NGCcoin.com/NCS.