Mint Marks When A Coin Should Have Them.

When it's supposed to have them & they don't. I found that you can go to:

http://en.wikipedia.org

Put in the search box the denomination your looking for, i.e., Roosevelt dimes. It will tell you within the article at what year the mint mark was added.

http://en.wikipedia.org/wiki/Roosevelt_dime

For instance, "since 1946 the Roosevelt dime has been minted every year. Through 1955 all three mints, Philadelphia, Denver, and San Francisco produced circulating coinage, and the latter two since that date. Beginning in 1968 San Francisco produced only proof coinage. Through 1964 "D" and "S" mintmarks can be found to the left of the torch. From 1968 on they appeared above the date. None were used in 1965-67, and Philadelphia did not show a mintmark until 1980. In 1982 an error left this "P" off a small number of dimes, which are now valuable."

Some dates that are supposed to have mintmarks occasionally do not. This can be due to a grease-filled die. You can identify one of these strikes by general weakness of the coin in certain areas with strong detail in other areas.

http://www.coincommunity.com/forum/...15423#123781

The most famous, besides the 1982 no mint mark Roosevelt dime, is the 1922 No D mint mark Wheat cent. And never forget the 1990 no S mint mark in the proof sets.

I cover all this information in my ebook A Beginners Guide To Pocket Change and Coin Collecting Treasures. Questions like this is the reason I wrote it.

Please don't remind me of the 1990 no S Lincoln Cent in the proof set as I had one that was purchased in 1990 at the Denver Mint and upon returning home from our trip I(we) accidently switched bags when unloading with relatives we were vacationing with. Needless to say, over a period of 15 years I have tried to get MY proof set back but to no avail. I get sick every time I think of it!