NCS Conservation: Even Highly Prized Coins May Develop Ugly Residues

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.

Even highly prized coins can develop unattractive residues. This gold Italy Duchy of Savoy 1 scudo d’or dated 1576 was recently submitted for NCS conservation to address the heavy red residues visible around the legends and devices. Opaque residues such as on this gold piece can hide original surfaces preventing the coin from displaying its true beauty. This kind of red residue is frequently seen on historical gold coins. By skillfully removing the unattractive residues, the piece was able stand out once again. Following conservation, this coin was able to grade numerically with NGC.

Italy Duchy of Savoy 1 Scudo d’or dated 1576 Before conservation Click images to enlarge.

Italy Duchy of Savoy 1 Scudo d’or 1576 After conservation Click images to enlarge.

Coins can develop a great many kinds of residues through inferior long-term storage methods. This silver Germany 1914D Mark was submitted to NCS because of a greenish white residue that had developed in a stripe across the obverse. The tell-tale stripe is often indicative of a coin that had been held fast by adhesive tape, though in the absence of any adhesive the stripe may likely have been caused by PVC flip storage. Careful conservation work was able to have this stripe removed and the mild coloring corrected to reveal a bright lustrous coin. This coin was able to grade well with NGC following the professional conservation.

Germany 1914D Mark Before conservation Click images to enlarge.

Germany 1914D Mark After conservation Click images to enlarge.

Long-term storage in inferior coin holders can cause potentially damaging residues. This Proof copper-nickel Serbia 1884 10 Para was recently submitted to NCS to remove a greasy appearing residue that had developed relatively evenly on both sides. Copper-nickel coins tend to be more susceptible to corrosion development from the presence of heavy residues so it is important to remove this residue. Luckily for this Balkan piece, the residue had not caused corrosion and this coin was able to grade well with NGC.

Serbia 1884 Proof 10 Para Before conservation Click images to enlarge.

Serbia 1884 Proof 10 Para After conservation Click images to enlarge.

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

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