Real, But Not: An Introduction to Altered Coins

While searching through loose change, an old Mercury dime catches your attention—even better, it’s dated 1916. Better still, is that a “D” mintmark? Oh wait, never mind. It’s just a 1916-(P) Mercury dime, and that little difference makes it worth about 200 times less. If only you could snap your fingers and add a “D,” you’d have an extremely valuable piece. 

Some unscrupulous individuals have done and continue to do exactly this, altering genuine coins to make them more valuable varieties and improve their appearance. These alterations can often fool even advanced collectors, as a genuine coin can cause us to let our guard down and become susceptible to missing a small modification. Although alterations can be difficult to detect, these tips can help you determine whether a coin you’re looking at has been tampered with.

Date/Mintmark Alterations

The example of a 1916 dime above is one of the most common pieces altered. When examining expensive coins, pay special attention to the area where a mintmark is (or would be) present. For added mintmarks, look for evidence that the mintmark does not appear to be part of the coin. Often, this manifests through differences in color, metal flow patterns, or a seam visible around the edge of the mintmark. 

More advanced criminals can use a technique in which a mintmark is embossed, or pushed up from the inside of the coin. This is done through a process in which an alterer drills a tiny hole into the edge of a coin, and then inserts a tool into the hole to raise a mintmark. Embossed mintmarks can be extremely hard to detect, as traditional methods of detecting alterations, like examining metal flow, will not work. To spot an embossed mintmark, compare the mintmark’s shape and design with genuine coins.

Many coin series, like Lincoln cents for example, have had the design of their mintmarks changed over their run. Spotting a mintmark that wasn’t used during the time of the coin’s minting will reveal that the mintmark was added. Additionally, the edge of the coin can be examined for tooling, as the hole drilled to emboss the mintmark is often filled relatively sloppily. Tooling commonly takes the appearance of disruptions in metal flow, unnatural color in a subject area, or artificial wear/hairlines. 

For cases where a mintmark was removed instead of added, look for traces of tooling in the area where the mintmark would have been. In any case of a potentially altered coin, comparing the suspect coin with certified examples and known fakes can be an extremely valuable tool in determining authenticity.

Instead of altering the mintmark on a coin like the 1916-P dime, forgers often attempt to change a coin’s date to make it more valuable. Although there are cases in which a forger removes and changes the entirety of a date, most often they only alter one digit (usually the last). In either scenario, checking again for tooling is a good practice. The spacing of the numbers or the font in an altered date can also appear off or lack consistency. Again, checking the coin against known genuine pieces can be beneficial in this situation.

Artificial Coloring

The rise of wildly toned coins in the market over the past few decades has led to an increase in forgers faking this toning. Without expensive tools like scanning electron microscopes, detecting fake toning, especially when it’s been done by experienced “coin doctors,” can prove almost impossible. However, to ensure you are not fooled by many of the sloppy examples for sale on sites like eBay, keep an eye out for overly bright, crayon-like colors and excessive amounts of pink and purple toning (colors that are rare in natural toning).

In many instances, fake toning can be performed on a coin with gases that allow a slabbed coin to remain slabbed throughout the process, leading to a false sense of security for a buyer. As a result, one should still exercise caution with slabbed coins, as extremely deceptive fake slabs have also become an issue in attempting to conceal altered coins. 

Conclusion

Though the world of altered coins can seem scary to new collectors, knowing the few simple tips described here can put you well on your way to detecting many low-level alterations. Practicing these strategies, in addition to being mindful of smart buying practices (such as buying from reputable dealers, buying in person, etc.), you can be proactive in spotting altered coins and increase your confidence in the integrity of your collection.