1918 Mercury Head Winged Liberty Dime Image
1942/1 Mercury Dime Image
Images courtesy of Heritage Auctions
Mercury Dime Facts:
In 1916, a new Dime design was introduced to replace the old Barber design that had been in use since 1892. Designed by A.A. Weinman, the new design featured a portrait of Liberty facing left, wearing a winged cap.  Because of the resemblance to the Roman god, Mercury, the coin became known popularly as the "Mercury Head" Dime.  The reverse blends a Roman fasces (ax surrounded by a tied bundle of sticks) and an olive branch, indicating America's military readiness but also their desire for peace. 

The Mercury Head Dime series is one of the most popular in all of American numismatics.  Apart from the 1916-D and 1942 overdates, most dates are obtained with little difficulty.  However, several of the dates are extremely rare in high grade.  The most desirable issues are those with Full Split Bands on the reverse, which means all of the bands that hold the fasces together on the reverse must be clearly and completely separated.  While much attention is focused on the central bands, the bands on the ends of the fasces must be separated, as well.  Again, many dates are extremely rare in Gem condition with Full Split Bands.

Designer: Adolph Alexander Weinman

Diameter: 17.9 millimeters

Metal content:
Silver - 90%
Copper - 10%

Weight: 2.50 grams

Edge: Reeded

Mint marks: the mint mark appears as a small letter just to the right of the E of ONE on the reverse:

None = Philadelphia
S = San Francisco
D = Denver

Cherry Picker's List:

1916-D This is the key to the series and it is eagerly sought after in all grades.
1921 Scarce, semi-key issue.
1921-D Scarce, semi-key issue.
1942 Look for the rare 1942/1 over date on circulation strikes only.
1942-D Look for the rare 1942/1-D over date.
1945 Uncirculated examples with Full Split Bands are very rare.
1945-S Comes with a normally sized mint mark and a very tiny "Micro S".
1926-S  (Look for this coin in higher grades, (Book Value) BV will dramatically increase.)

1942/1 Over date Mercury Dime

Mint Mark location

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