That would be the 1916-D with a mintage of 264,000. However, the 1941/1942 overstrike error with an unknown mintage is also in demand by collectors. More information can be found at this website : http://coins.about.com/od/coinvalues/qt/mercury_keys.htm
1943 is a common date for Mercury dimes and there are no significant varieties.
a 1916-D mercury dime
Do a Google image search for "Mercury Dime" and you will see the photo of the dime.
Most likely (with the exception of a few errors and rare die varieties) the rarest dime is the 1894-S dime with only 24 made.
The 1916-D Mercury dime is 1.35mm thick and has a diameter of 17.9mm.
a 1917 us dime is called a mercury dime. its not that rare so it is worth about a dollar
a 1936 dime is called a mercury dime. they aren't rare so they are worth around a dollar
1943 is a common date for Mercury dimes and there are no significant varieties.
1942 is a very common date Mercury dime most are worth about a dollar just for the silver. But it could be worth something since that was around/during WWII.
I' guessing old dates such as 1744 or 1600 or older.
1944 is a common date for Mercury dimes and there are no significant varieties.
The Winged Liberty, or Mercury Dime. Most people call it the Mercury Dime, but its real name is the Winged Liberty dime.
7-2-11>>> The last Mercury dime was struck in 1945. A 1958 dime is a Roosevelt dime (1946 to date) and is common, most are only valued for the silver, about $2.00
Roosevelt appered on the dime for the first time in 1946. The 1937-D Mercury Dime is not rare and most show heavy wear and are valued at $2.00-$9.00
a 1916-D mercury dime
If it's a U.S. dime with a date of 1944, it's a Mercury dime.
No rare 1941-S dimes. The 1941-S Mercury dime does have large and small mintmark varieties as do all coins (except the half dollar) that were struck in San Francisco in 1941, they have no added value.