NCS Conservation: September Highlights

Posted on 9/10/2019

View this month’s NCS Conservation highlights.

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 numismatic items that were recently conserved by NCS and graded by NGC.

The optimum holder for long-term storage is one that is as airtight as possible. Original mint packaging is quite often a less-than-ideal coin holder for long-term storage.

This 1993-S James Madison Silver Commemorative Half Dollar arrived at NCS with a terrible case of residue likely caused by years of storage in original mint packaging. Residues such as this are caused by interaction of environmental chemicals while the coin is resting in holders that are far from airtight. Expert conservation must be performed to remove the thick opaque residues without creating damage to the mirrored surface underneath. This commemorative coin was able to grade very well with NGC after professional NCS conservation work.

1993-S James Madison Silver Commemorative Half Dollar
Before conservation
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1993-S James Madison Silver Commemorative Half Dollar
After conservation
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This 1974 Iceland Commemorative Silver 500 Kronur issued in honor of the 1,100-year anniversary of settlement on the island had been in poor long-term storage holders, but instead of developing residues, this coin developed an unattractive yellow hue. Removing unattractive toning from the surface of modern coins requires specific skills to successfully remove the offending color without damaging the surfaces. Toning on modern coins can hide the presence of mild environmental damage. Fortunately for this Icelandic coin, the toning was not hiding any environmental damage and the result after careful conservation is a bright white reflective proof coin as it was originally issued. Following conservation, this coin was able to grade very well with NGC.

Iceland 1974 Commemorative Silver 500 Kronur
Before conservation
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Iceland 1974 Commemorative Silver 500 Kronur
After conservation
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Modern coins often develop residues that aren't opaque but can be just as potentially damaging for long-term storage. This 2000 Silver Commemorative Punt from Ireland was submitted to NCS to address the blotchy blue residue that had developed in the fields from poor storage. Removing colored residues such as these can usually be safely performed by the conservators at NCS. Following skillful conservation work, this Irish modern coin was once again looking its best and graded well in an NGC holder.

Ireland 2000 Silver Commemorative Punt
Before conservation
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Ireland 2000 Silver Commemorative Punt
After conservation
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For more information about NCS, visit NGCcoin.com/NCS.


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