Expert: PAPAJACK - 1/25/2008

Question
Papajack, I have come across a 1990 lincoln coin with no mint mark and I am having a hard time finding some clear information on it. I am not exactly clear on the difference between proof and mint mark (???) Are just the rare ones already in a case or is it possible to find one? the "frosty" picture? I am not sure either. The cameo is very clear. If there are ones that are normally without a mint mark and those that don't because of error are there any other ways to find out? Thank you for your time. Angel

Answer
Hello Angel,                                              

I am not sure of your exact question but here is some clarification. Mint Mark and Proof are seperate attributes.
Proof coins are specially made, they have a Cameo (Frosted Matte) raised image on a polished flat mirror-like field. And show a much nicer image than the business strike coin. Each starts with a polished coin blank and is struck with proof dies at least twice for more detail.

The Proof sets since 1968 come in a hard plastic holder, they all are to have an S mint mark since all proof coins are made in the San Francisco mint.  They are issued in copper-core nickel clad, as the circulated coins are, and in 90% silver as well.

Whereas coins made for circulation (business strike) are the common qualities of coin in your pocket.
They are made at 2 mints Philadelphia and Denver.  The Philadelphia issue cents have no mint mark and the Denver issue cent has a “D” usually below the date.  

All the coins made for circulation each year are also available from the U.S. Mint in two versions, Proof sets and Mint Uncirculated Sets.
See:    http://www.usmint.gov

So all the one cent coins made at the Philadelphia Mint facility do not get any mint mark.
All the one cent coins made at the Denver Mint have a D mint mark.

The Proof one cent coins made at the San Francisco Mint have an S mint mark.

I have seen Proof coins in circulation. Sometimes someone spends them and I get them in change. So it is possible to find them.
There are cases where the Proof Dies are used to make coins for circulation as well.
Each coin has to be looked at carefully to be properly attributed for special characteristics that may make it more valuable.

Please if you need any more clarification on this question feel free to write me back.

Thank You and Good Luck

PapaJack