The 1942/1 Mercury Dime is a rare overdate coin which shows the numeral “2 over 1″ for the final digit of the date. The variety was created when two obverse dies were impressed with a 1941 dated hub and then a 1942 dated hub.
By far, this is the most widely known and popular variety of the series. It is listed within the Red Book, which heightens awareness of the variety even for collectors who have not studied the series.
The overdate occurred at both the Philadelphia and Denver Mints. The Philadelphia minted version is much more bold and obvious, and was detected in circulation shorly after release. In March 1943, the discovery was publicized within a Numismatic Scrapbook article, which led many other examples to be identified and saved. The Denver minted version is less obvious and was actually not detected for some time.
Today, the 1942/1-D carries a slight premium at lower grade levels, but in gem condition, the Philadelphia issue is scarcer and commands a premium.
The finest graded examples of the 1942/1 Mercury Dime are a handful that have graded MS66 with Full Bands by PCGS and NGC. One of these examples graded by PCGS sold for $60,950 at an auction held in January 2011.