Errors & Varieties: The 1942/1 and 1942/1-D Mercury Dimes

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The United States Mint created two outstanding overdate varieties with 1942/1 Mercury Dimes from both the Philadelphia and Denver Mints.

By Edward Van Orden - August 16, 2024
Original link: https://www.pcgs.com/news/the-1942-1-and-1942-1-d-mercury-dimes

Overdated coins are among the most sought-after varieties in American numismatics. The expensive and time-consuming process of creating new dies is why early issues, such as the 1796/5 Draped Bust Half Dime and 1802/0 Draped Bust Half Cent, were made by repunching the current year into a die of an earlier year. By the early 20th century, technological advancements in die production rendered the need to repunch dies unnecessary. However, a few overdated dies still managed to be created.

The evolution of die making is foundational to the field of varieties and essentially brought about the creation of two of the most famous (and valuable) 20th-century overdates: the 1942/1 and 1942/1-D Mercury Dimes.

Closeup detail of the 1942/1 Philadelphia overdate.

But how did they come to be? We need to look back to die-making practices of yore to better understand how the 1942 overdate dimes were born, and we start with looking at the design features of each 1793 Chain Cent obverse and reverse die, which were completely hand-engraved. But this method of die making was time-consuming and costly. In order to produce dies more efficiently for the 1793 Wreath Cents that came along, hubbing, which is the process of creating numerous dies with the same design, was employed. This involved hand engraving the actual size of the coin’s obverse or reverse device (the bust or wreath) onto the end of a solid steel cylinder to create the master hub.

Closeup detail of the 1942/1-D overdate.

This hub was then pressed, or hubbed, into a steel blank multiple times to fully impress the incused image, creating the working dies from which coins would be struck. When mintages for future mint issues were expected to be exponentially higher, two more hubbing stages were employed to accommodate the need for more working dies. The master hub was used to create, instead of working dies, numerous master dies (in incuse). Each master die was used to create working hubs (in relief), which in turn were used to press the working dies (in incuse).

To make the die creation process even more efficient for future mint issues, the other features of a die’s design, such as the stars, lettering, dentils, arrows, etc., were also directly engraved into the master hub. By 1909, the date was applied to the master dies, and in 1985, the mintmark began following suit.

This brings us to the 1942/1 and 1942/1-D Mercury Dimes. How did these happen if date repunching was a thing of the past?

For many years, all working dies produced at the United States Mint were hubbed at least twice in order to provide a strong impression of the image. During the final months of 1941, when both 1941 and 1942 dies were being prepared in Philadelphia, two Mercury Dime obverse working dies were pressed with a 1941-dated hub, then a 1942-dated hub. One of the working dies was used to strike the 1942/1 issue, and the other was shipped to Denver to produce the 1942/1-D. Incidentally, this use of two different-dated working obverse hubs is precisely how the two other famous 20th-century overdates, the 1918/7-D Buffalo Nickel and 1918/7-S Standing Liberty Quarter, came to be.

Regardless of whether these overdated issues were made due to the intense wartime work loads of the mint’s engraving department or simply human error, the 1942/1 and 1942/1-D Mercury Dimes are arguably among the most desired overdates in American numismatics.