Conservation Showcase: Korea 1906 1 Chon

BEFORE CONSERVATION
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AFTER CONSERVATION
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Copper coins from around the world can develop some very similar problems. Environmental conditions such as humidity can combine and create some surface conditions numismatists would rather not see. As a copper coin is exposed to the environment it will naturally turn from a bright red to a deep brown. Adding moisture to the mix can create spots of green that with right conditions will continue to oxidize permanently damaging the surface of the coin.

This 1 Chon coin of Korea dated the Tenth Year of Kuang Mu, or the equivalent of 1906 had developed a deep brown color. Moisture also created several small green spots indicating the earliest stages of corrosion. Luckily for this piece, the corrosion had not penetrated into the surface of the coin. After careful removal of residues and taking steps to keep any corrosion from progressing in the future, the coin was left with an even pleasing color. This coin was able to grade well with NGC following the conservation.