The Fascinating World of Insects and Minting Errors: The Misaligned Stag Beetle
By Sebastian Wieschowski
When coin collector Thomas Egeler inspected his freshly minted five-euro coins from the “Fascinating World of Insects” series, he couldn’t believe his eyes: in three rolls, he found several examples of the stag beetle with an obvious minting error—the intricate colours of the insect were misaligned.
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Dezentrierter Fehldruck: Bei diesem Exemplar ist die matte Oberfläche der Körperteile des Insekts, die eigentlich bedruckt werden sollten, gut zu erkennen. Foto: Thomas Egeler.
Egeler set out to find more information and soon discovered he wasn’t the only one to have stumbled upon this numismatic curiosity. A similar coin was being offered at an online auction for €49. At least one dealer had also found some in a roll: “Currently, 33 coins with this error are known,” Egeler summarises. And that’s not all—an uncoloured stag beetle coin has surfaced in another online auction with an asking price of €299—a substantial value increase from its face value of five euros.
Insect coins with coloured applications are once again making headlines. In 2023, some examples of the “Red Mason Bee” coin exhibited a visual flaw—the paint was peeling off, seemingly because it hadn’t dried properly. Several major coin trading houses confirmed the problem to Coins Weekly, reporting that up to a quarter or even a third of their supplied coins were affected. One mail-order dealer turned this quality issue into a sales pitch, offering a “quality guarantee” for its “checked specimens.”
Reflective Surfaces Confuse the Printing Machine
This latest issue with the colour application on the “Fascinating World of Insects” coins isn’t as widespread as the 2023 incident, but it does reveal interesting insights into the production of coloured coins. “The coins are first minted as regular coins and then printed using a digital process,” explains Reinhard Riffel from the Bavarian State Mint to Coins Weekly. The printing process is largely automated. “During production, it can occasionally happen that the camera system misreads the coin’s position due to strong surface reflections, causing the print to be misaligned,” Riffel notes.
Such deviations are rare and are usually detected during production or packaging. “However, it can’t be ruled out that some examples slipped through both the mechanical and manual quality controls,” Riffel concedes. He estimates the number of affected coins to be extremely low—on the scale of “parts per million.” For a production run in the millions, this would mean only a handful of coins.
Deluxe Error: Part of the leg is missing in this example. Photo: Thomas Egeler.
Applying Colour Is Technically Challenging
In his discussion with Coins Weekly, Reinhard Riffel highlighted that applying colour to embossed coins is technically demanding, especially in mass production. “For other coloured coins, such as the brilliantly executed 25-cent coin from the Bahamas in 2024, the area intended for colour application is not pre-embossed but features a smooth, simple surface, allowing for some flexibility in positioning during printing,” Riffel explains.
On this 25 cent coin from the Bahamas (2024) and a dollar coin from Canada (2022), it is clear that some ‘play’ has been allowed for in the position of the print so that slight off-centring of the print is not noticeable. Photos: Reinhard Riffel / Bavarian State Mint
While the misaligned print on the insect coins is rare yet understandable from the production perspective, Riffel was puzzled by the entirely uncoloured coin. That a coin could bypass the colouring stage, end up in packaging, and make its way to the Bundesbank for distribution seems unlikely, he says.
Uncoloured stag beetle coins reveal a fine surface texture. Photo: Reinhard Riffel/Bavarian State Mint.
A Colour Coin Without Colour—How Did It Happen?
The question remains: how did this minting error—or more accurately, “non-printing error”—occur? Was the paint removed afterward? The surface appears conspicuously flat, which could theoretically result from treatment with fine polishing sand.
An even more dramatic possibility is that the coin somehow left the mint before the colouring stage. Over the years, exotic minting errors have appeared in coin trading that defy standard explanations, such as a one-euro coin design struck on a 50-cent blank or a one-euro blank featuring designs from two different countries. These highly exotic specimens are often listed at lofty prices in the hundreds or even thousands of euros—whether they find buyers is another question.
Edge inscriptions matter: Sometimes the text aligns with the motif…
The Rarer the Error, the Greater the Value Speculation
How the uncoloured stag beetle came to be remains uncertain. Reinhard Riffel advises caution when purchasing high-priced minting errors. Moreover, it’s unclear if errors in this price range will sell successfully. For example, the misaligned insect coin found a buyer at a “buy now” price of €49.90.
…and sometimes it’s upside down. Photos: Thomas Egeler.
Interestingly, during a closer review of his error coins, Thomas Egeler discovered another detail: there appear to be two variations of the edge inscription. “I own seven coins where the text aligns with the motif and 14 where it’s upside down,” he reports. ‘The coins or blanks are first edge-marked as a batch and then minted as a batch. When the edge-marked blanks are fed into the minting machine, no attention is paid to the direction of the edge lettering, so there are always two variants of each edge-marked coin,’ explains Reinhard Riffel from the Bavarian Central Mint. Thanks to minting errors and misprints, coin collecting is always full of surprises.
