Grading Color-Enhanced Coins a Challenge

How do you grade and authenticate a color-enhanced coin? This is a recent development needing to be addressed. Color enhanced technology has advanced to the stage where coins can be mass produced for circulation with this embellishment.

Color enhancement being applied to a coin is a relatively new development that can be traced to the Japanese 17th century gold oban coins on which black ink calligraphy was applied by hand.

In more modern history it was Derek Pobjoy and his privately owned Pobjoy Mint that pioneered color enhancement on coins. The non-circulation legal tender nickel composition 1990 Penny Black crown commemorative marks the anniversary of the first applied postage stamp. Since the stamp is referred to as the penny black due to its color, the coin was issued with a gray to black enhancement applied on the reverse on the image of the stamp.

While the Popjoy coin was a first, the color enhancement has been seen to fade over time on some of these coins.

The process was initially labor intensive, making color enhancement more of a novelty to be applied to NCLT commemoratives than to circulation strike coins as some form of counterfeit deterrent. All that changed when the Royal Canadian Mint began using a picoseconds laser technique to add color without the use of inks, dyes, or pigments.

In 2004 the RCM issued a 25-cent coin for circulation on which a red-color enhanced image of a poppy was imbedded in the center of a maple leaf over a banner reading ‘Remember/Souvenir’ on the reverse. The approximately 300,000 coins minted were a novelty at first, having been distributed exclusively at Tim Horton restaurants across the country. At that time, it was revealed the coins had been processed using “a high speed, computer controlled, and precision inkjet process.”

U.S. Army contractors in Canada filed a confidential espionage report in which the color-enhanced coins were described as “anomalous” and “filled with something man-made that looked like nano-technology.”

In 2017 circulation color enhanced glow-in-the-dark coins marking the 150th anniversary of Canadian Confederation complicated the technology further. Other coin manufacturers have followed Canada’s pioneering, using various color applications.

The question of grading the quality of color enhancement has became more widespread following the release of the U.S. 2020 Basketball Hall of Fame half dollars and silver dollars.

David Camire is Numismatic Conservation Services president and Numismatic Guaranty Corporation finalizer. According to Camire, “In general, we grade colorized coins the same as we do non-colorized coins. There are, however, situations unique to colorized: if the colorization is off center, if it is not correctly applied to the coin, or if there are any missing pieces to the colorization (including a lack of colorization).

“For the first case, depending how far misaligned the colorization is, the coin will either be straight graded (and may be limited to Mint State/Proof 69) or may be called a mint error (if the misalignment is drastic).

“In the second scenario, if the coin is missing a small part (ie: paint is chipped) then the grade will be affected and will not grade higher than MS/PF69. If there is a significant loss of colorization, then the coin will not be gradable.

“Since there are multiple ways to apply colorization, there are times where the colorization will “fall off”. Additionally, color can often be removed from a coin (such as with Acetone). In both cases the coins will be deemed upgradable and returned as Missing Application.

“A word of caution. NGC will only grade officially colorized issues. In today’s market, there are many independent firms that colorize coins after minting. We will not grade these coins and they will be returned as ‘Colorized outside the Mint.’”

Those coins sold exclusively for collector consumption will require the quality of any color enhancement to be scrutinized, but high-grade colorized circulation strike coins will likely be the greater challenge to collect.