NCS Conservation: Saving Victims of Soft Flip Storage
Posted on 5/10/2022
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.
Long-term storage in soft flips containing PVC will lead to the formation of some unattractive and potentially corrosive residues. This silver Germany 1927A 3 Mark commemorating the 100-year anniversary of the establishment of the port city of Bremerhaven was recently submitted for NCS conservation to improve the appearance by removing a thick jade-green residue that had formed on both sides of the coin.
Heavy residues such as these can be troublesome to remove but the professional conservators at NCS have developed techniques to remove these residues without damaging the coin underneath. After successful PVC residue removal, this coin was revealed to be bright and subsequently able to grade well with NGC.
A green color and dull haze is often an indication of PVC residues. This silver 1810 Swiss Canton of Basel 3 Batzen was submitted to remove a uniform thick opaque residue wholly obscuring the surfaces. Likely long-term storage in poor quality coin holders caused this extensive residue to form. Following professional conservation to remove the obscuring residue while leaving the very subtle rosy toning, this Swiss silver coin was able to grade very well with NGC.
Modern coins often develop unattractive residues through poor storage. This copper-nickel Poland 10 Zloty issued in honor of the United Nations Food Agriculture Organization was recently sent to NCS to address heavy residues that had developed haphazardly over the entire surface including an unsightly fingerprint. Even Mint State strike coins can develop unsightly and damaging residues after years of storage in soft flips containing PVC. Luckily for this popular Polish coin, the residue had not irreversibly damaged the surface metal and following professional conservation this coin was able to grade well with NGC.
For more information about NCS, visit NGCcoin.com/NCS.
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