NCS Conservation: November 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 coins that were conserved by NCS and graded by NGC recently.

Haze development is a common result of long-term storage in a holder that is not air-tight and is one of the many things the conservators at NCS have developed techniques to remove without damaging the surface underneath with hairline scratches. The bluish haze that appears fairly evenly across both sides of this modern Thai coin is a prime example of that kind of development. Following conservation, this Thailand 1997 Silver 200 Baht issued in honor of the 50-year anniversary of UNICEF was able to be graded by NGC in its best possible state. This popular coin was graded very well by NGC after the professional NCS conservation work.

Thailand 1997 Silver 200 Baht Before conservation Click images to enlarge.

Thailand 1997 Silver 200 Baht After conservation Click images to enlarge.

The combination of time and poor storage can lead to the creation of unusual residues. This 1911 Netherlands East Indies (Indonesia today) silver Quarter Gulden had been poorly stored for some time, developing a particularly unattractive yellow-hued residue on top of a predominantly white coin. Thick residues are not only unattractive but can lead to permanent damage to the coin surface underneath. The technicians at NCS have developed specific techniques to tackle all sorts of issues and even this somewhat more unusual residue does not provide a great challenge. The residue was safely removed without damaging the coin's surface. Following conservation, this coin graded well with NGC.

Netherlands East Indies 1911 Silver ¼ Gulden Before conservation Click images to enlarge.

Netherlands East Indies 1911 Silver ¼ Gulden After conservation Click images to enlarge.

Fingerprints also are a common issue NCS conservators are called upon to address. This Thailand silver Half Baht dated BE2472 (1924) was submitted to NCS to address both an unattractive yellowish residue and a fingerprint in the field below the elephant. Fingerprints can be difficult to safely remove if the fingers' natural oils have etched into the surface of the coin's metal. Other times, fingerprints are not etched into the surface metal and can be removed safely. Luckily for this fine Thai silver coin, the fingerprint could be removed along with the offending residue, revealing a frosty white silver coin. Following conservation, this coin was able to be graded very well in an NGC holder.

Thailand (1924) Silver ½ Baht Dated BE2472 Before conservation Click images to enlarge.

Thailand (1924) Silver ½ Baht Dated BE2472 After conservation Click images to enlarge.

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