NCS Conservation: January Highlights

Posted on 1/21/2020

A few recent NCS conservation projects involving residues and encrustations.

Numismatic Conservation Services™ (NCS®) uses a variety of proprietary techniques to remove harmful surface 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 Corporation® (NGC®), an independent affiliate of NCS, for grading and encapsulation.

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

Numismatists are acutely aware of the kinds of residues that can develop through the use of inferior coin holders such as the development of PVC, but before a coin is a prized part of a collection, any number of unattractive and potentially damaging residues can develop. This 1915 Cuba Peso developed a thick residue through years of improper storage. Thick residues such as these can permanently damage the original surface of the coin hiding just underneath. This large silver Cuban piece was able to have the residue removed and reveal a bright white coin. This coin was able to grade well numerically with NGC following skilled conservation work.

Cuba 1915 Peso
Before conservation
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Cuba 1915 Peso
After conservation
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The mirrored fields of modern Proof issues are especially susceptible to the development of ugly residues. Long-term storage in likely an original mint holder left this silver 2000 Costa Rica 5000 Colones Central Bank Anniversary commemorative with hazy, opaque residues covering the mirrored fields on both sides. The technicians at NCS have developed specific techniques to safely remove all sorts of residues without damaging the surface underneath. This residue was able to be removed safely and, after conservation, the coin graded very well with NGC.

Costa Rica 2000 5000 Colones Central Bank Anniversary Commemorative
Before conservation
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Costa Rica 2000 5000 Colones Central Bank Anniversary Commemorative
After conservation
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Coins that have been salvaged from the seafloor provide a unique challenge for the conservator. This gold Colombian 4 Escudo produced during the reign of Ferdinand (1741-56) is a clear sea salvage piece. In several spots, the spiral impression of a tiny seashell can be seen in encrustations. Gold, being the least reactive of all the metals that are typically used to make coins, usually yields the best results after conservation. Once the encrustations were able to be carefully removed, the coin is revealed in full high relief beauty. This coin was able to grade numerically with NGC following professional conservation.

Colombian (1741-56) 4 Escudo
Before conservation
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Colombian (1741-56) 4 Escudo
After conservation
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For more information about NCS, visit NGCcoin.com/NCS.


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