Making coining dies can involve incredibly detailed work given the size of some elements like dates and mint marks. While modern techniques have made the task easier, in earlier days some elements that resided near the coins’ rims were often hand punched to preserve their clarity.
Modern equipment has eliminated the need for hand punching dies, but when it was done it was done by humans, and humans make mistakes. In coin collecting this has given us an entire class of “error coins”: Punching Errors.
Early Re-Punches
In the early days of US coinage, dies were used until they wore out. This meant that the same die could be used from one year to the next, requiring a date change. The change was made by re-punching the die, usually to change the last digit of the year. Sometimes the result was barely noticeable. This was done frequently enough that detectable date re-punches are not that uncommon on earlier coins and are not generally considered errors, per se. But they’re still collectible.
Double-Punching Errors
Double-punching mistakes typically occur when an initial punch doesn’t set deeply enough into the die creating a need to strike the punch a second (or third) time. If the punch is misaligned or bounces during subsequent strikes, a doubling of the element can occur and is transferred to the coin.
Double Punches vs Doubled Dies
Punching is done separately from making the coin die itself. Therefore doubled dies will exhibit doubling across the coin’s face whereas double punches will be confined to the punched area alone. This is an important distinction for collectors as doubled dies are generally rarer than punching errors.
Incorrect Punch
Occasionally mint workers have chosen a punch that is the wrong size for the letter or number they are adding. Famous examples include the “Micro S” dime of 1945. Instead of using the correct S mintmark die punch, one intended for use on Philippine coins was substituted, resulting in a smaller-than-normal mintmark. Two errors are known to have occurred at New Orleans when a mintmark punch intended for quarters may have been used on the rare 1892 “Micro O” Barber half dollar and on a 1905 Barber dime (the dime actually had a larger mintmark than the quarter).
Double-Punched Mint Marks
Before additional US Mint facilities opened beginning in 1838, the dies had no indication of where the coins were made. It was decided that coins made outside Philadelphia should carry small letters indicating the branch of manufacture.
Dies were sent to the satellite mints from Philadelphia without the identification, so the mintmarks were hand-punched on site. The dies were extremely hard in order to stand up to wear and sometimes the mintmark punch had to be struck a second or third time, occasionally resulting in misaligned punches such as the one shown here on Wikipedia..
Overdates and over mintmarks
Overdates were common in early coins and were discussed above. An over mintmark occurs when a second mintmark is punched over a previous mintmark following the transfer of a die from one mint to another. The repunched mintmark may hide the original mark completely, but sometimes traces of the original remain. Examples include an O-over-CC silver dollar from 1900 and a 1938 Buffalo nickel with a D punched over an S.
Collectability and Value of Punching Errors
Like all collectible things, the values of error coins vary greatly based on demand and rarity. When it comes to punching errors, millions of coins were released with known flaws, but several are highly sought. These include the 1892 “Micro O” Barber half dollar; an MS-67 coin sold for over $97,000 at auction in 2005. A “Micro O” dime brought over $12,000 that same year.
An MS-67 1900 O-over-CC dollar sold for $37,375 in 2011, and an MS-68 1938 Buffalo nickel D-over-S pulled in $25,300 in 2004.
But grade is everything when buying coins, and even rarer mis-punched coins can be had in lower grades for very reasonable prices, so don’t be afraid to start low and upgrade as your budget permits.
Collecting Error Coins
Always exercise caution when buying error coins because many types are easily faked. But there are thousands of varieties still in circulation, so if collecting them appeals to you, learn as much as you can about the subject. Books and articles are available online, and there’s an organization called CONECA devoted to the education of error and variety coin collectors. Visit their website, conecaonline.org, for more information.
