Conservation Showcase: 1923 D $20 Double Eagle

Posted on 8/2/2010

A recent example from our conservation laboratory.

NCS Conservation Showcase NCS Conservation Showcase
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NCS Conservation Showcase NCS Conservation Showcase

A commonly encountered issue with gold coins is the dreaded copper spot. Caused likely by slight inconsistency in the alloy of gold with copper and silver, these small reddish spots can develop on the surface of a gold coin over time. Removal of the spots can be time consuming, but careful removal can leave a coin with much greater eye appeal.

This 1923 $20 from the Denver Mint was recently submitted to NCS for removal of several copper spots most notably in Lady Liberty’s dress on the obverse and above the eagle in flight on the reverse. The conservators at NCS have been able to safely remove the spots from the surface of this coin leaving a coin with more pleasing and even surfaces. This coin was able to grade numerically well with NGC following the conservation.

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