NCS Conservation: Three Gold Coins Returned to Brilliance

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.

Gold is justifiably thought of as the most stable of coin metals, but even gold coins resistant to corrosion can develop shocking residues. This Austrian 1912 Gold Ducat had developed a thick, detail-obscuring, orange-red residue over much of the surface. Residues such as this can advance on gold coins likely long before the coin was a part of a numismatic collection.

The conservators at NCS have developed techniques to remove such extreme residue from the surface of gold coins without causing any permanent irreversible damage to the surface underneath. Following professional conservation this Austrian gold coin was bright and lustrous and was able to grade well with NGC.

Austrian 1912 Gold Ducat Before conservation Click images to enlarge.

Austrian 1912 Gold Ducat After conservation Click images to enlarge.

Poor long-term storage conditions often lead to the development of many kinds of unattractive detriments. Orange and red spots can develop on the surface of gold coins both modern, such as this Polish gold 200 Zloty commemorative, and vintage alike. The so called “copper spot” can appear as a small dot of orange red color or in larger swaths of color, and both iterations can be seen on the surface of this Polish gold commemorative. Careful conservation work was able to remove the red color without scratching the delicate proof surfaces underneath. Following professional conservation, the coin was able to grade very well with NGC.

Polish 2000 Gold Proof 200 Zloty Before conservation Click images to enlarge.

Polish 2000 Gold Proof 200 Zloty After conservation Click images to enlarge.

Many residues develop passively through environmental exposure due to improper storage methods. Yet, other residues, such as glue, develop rather actively through direct action. This 1916 Great Britain Gold Sovereign was recently submitted for NCS conservation to address a large area of glue present largely on the fields of the reverse. Luckily, NCS conservators have developed techniques to safely remove these kinds of sticky residues without damaging the surface underneath. Following professional conservation, this British gold piece has a natural look and damage-free surface. Following conservation this coin was able to grade well with NGC.

Great Britain 1916 Gold Sovereign Before conservation Click images to enlarge.

Great Britain 1916 Gold Sovereign After conservation Click images to enlarge.

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