NCS Conservation: Lacquer

Long before third-party certification companies like NGC offered holders that provided long-term protection for coins, some collectors applied a coat of clear lacquer to a coin's surface(s) in an attempt to protect it and prevent tarnishing. In theory this application may seem to be a great idea but in reality the lacquer could change the surfaces of the coin over time.

A lacquered coin will often appear to be wet or have a slick halo or doubling effect around the legends and devices. Depending on the skill of the person who applied the lacquer, bubbles or brush strokes can be sometimes seen. Some substances will also leave a rainbow or oil slick-like appearance on the surfaces, most notably in the fields.

Before conservation Click images to enlarge.

Romania 1869 Pattern 2 Lei A thick layer of lacquer gives the sharp edges around the letters in the legends a doubled appearance. After conservation Click images to enlarge.

Some of the problems caused by lacquer become much more obvious over time. Lacquer has a tendency to darken, which leads to an unnatural yellow or brown hue on the entire surface of a coin. Uneven application of the lacquer can result in pieces that flake off. The exposed metal will then oxidize and tone unevenly, causing visually striking geometric patterns on the surface. In some cases, this stark pattern can lead to environmental damage. It is also not unusual for lacquer to trap moisture or other catalysts, which leads to active corrosion underneath the lacquer. In these cases the presence of lacquer will prevent a coin from certifying with NGC.

1936 10C Proof Uneven application of lacquer left a portion of the reverse rim exposed, which resulted in dark toning in the area. left: Before conservation; right: After conservation Click images to enlarge.

German States Saxony-Albertine 1913E 3 Mark Pieces of lacquer broke off over time and exposed the metal to the enviornment, which resulted in a strange geometric pattern of staining on the surface. left: Before conservation; right: After conservation Click images to enlarge.

From the 19th century to the modern era, mints around the world have applied lacquer to specially created coins for presentation purposes or issues specifically made for collectors. When lacquer has been applied directly by the mint, the dangers of trapping corrosion beneath it are virtually eliminated. However, even coins lacquered by mints can have pieces of the lacquer break off, exposing the fragile surfaces to the environment, or the lacquer can develop an unattractive yellow color.

Removal of lacquer is generally recommended for coins that were lacquered subsequent to production or for coins where the lacquer has yellowed or flaked off. In some cases, the lacquer may have left the coin with slightly darker toning than it would normally have had, but the careful removal of the lacquer by NCS will still usually result in improvements. In most cases, removal of the lacquer by NCS will leave the coin looking significantly better—just as good as it did before the lacquer was applied.