NCS Conservation Showcase: Poland 1979 100 Zloty Proba

BEFORE CONSERVATION
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AFTER CONSERVATION
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Popular with numismatists of Polish coins are the “proba” or pattern series. These are examples of coins that might have been made specifically for collectors. As with many modern issues these coins are prone to the development of hazing residues that are unattractive, potentially damaging, and detrimental to their grading.

Years of less than ideal storage had left this 1979 Polish 100 Zloty commemorative coin with the development of unusual opaque blue residues. These residues are unattractive and create the right conditions for irreversible damage to the original surfaces. Luckily careful conservation work was able to remove the residues with very little affect on the original mirrored surface. Following conservation this coin was able to grade with NGC with standard numeric grading.

NCS is an independent member of the Certified Collectibles Group.