Philadelphia the inconsistent?

As soon as the calendar changes the page in a few days and 2014 begins, the regular usage of the “P” mintmark for Philadelphia will mark 35 years since it began.

That’s a long time.

That’s what can tax the memories of old-timers and confuse newcomers.

I had an email question:

“A coin with no mintmark is listed as a P? How does that differ from a coin issued by the “P” mint?”

It sounds like a trick question. For most of U.S. numismatic history, coins issued without a mintmark were the product of the Philadelphia Mint.

There was a special exception for silver war nickels of 1942-1945 when large mintmarks were used above the dome of Monticello, including a “P,” to denote the temporary silver composition of the denomination.

Change came again in the late 1970s when it was decided that as a matter of policy the Philadelphia Mint would begin using a “P” mintmark on a regular basis.

The first coin to feature the “P” mintmark was the new 1979 Anthony dollar. In 1980 the nickel, dime, quarter and half dollar joined the group using the “P” mintmark.

No mintmark was put on the cent as a bow to tradition.

Nowadays people add the “P” designation when they list coins that actually have no mintmark on them to indicate the mint that made them. This is both a courtesy and a necessity as anyone who has ever received a letter asking what the mint made a coin that was simply referred to by the date.

Old-timers know that a date appearing alone is a Philadelphia product.

Unfortunately, the Mint is not consistent in other ways. West Point silver, gold and platinum bullion coins have no mintmark on them, but then neither does the more recent San Francisco silver bullion American Eagles.

As time goes on, the old handy rule of thumb that a date listed without a mintmark means the coin was struck at Philadelphia will need more and more explanation.

Buzz blogger Dave Harper is winner of the 2013 Numismatic Literary Guild Award for Best Blog and is editor of the weekly newspaper "Numismatic News."