PROOF COINS 

   To understand the difference between a proof and un-circulated coin, let's first answer the question,

"What is an un-circulated coin?"

   Uncirculated means a coin has not had any wear, such as the wear a coin might experience when it is used in commerce. Handling a coin, as well as improperly storing a coin, can result in wear on the surface of the coin.  This wear, even if very minor, will cause a coin to no longer grade uncirculated.

"Bag Marks"

   When coins are minted they often bump into each other and receive small nicks and abrasion marks during the production process. These marks also occur as coins are transported in large canvas bags.  These marks, sometimes called "bag marks", are more noticeable on larger coins, such as half dollars and dollars.  Typical "bag marks" do not keep a coin from grading uncirculated.  However, they can be an indicator of how high of a grade the un-circulated coin might receive.

   Current accepted grading standards provide for a range of uncirculated grades, from the grade of MS-60 to MS-70.  MS60 would be a lower grade (yet still) un-circulated coin with normal bag marks for that type of coin.  Anything below MS-60 would not be considered uncirculated. MS70 would be the perfect "ideal" coin. Some coins are rare in grades MS65 to MS70, and even unheard of in MS70 grade.  (The attribute "MS" stands for "mint state".)

   An uncirculated coin may show tarnish, toning, spotting, or discoloration and still remain in uncirculated condition.  Experts recommend you "never clean a tarnished coin", because most cleaning will cause wear on a coin, and thus lower its grade (and often its value).

What's a proof coin?

   A newly minted proof coin is also Un-circulated, however it is the way it is made that causes a difference in appearance and qualifies it as a "proof".  To understand this, let's look at how coins are made.  Coins are produced when two dies strike a blank piece of metal with tremendous force. One die is engraved with the front (obverse) design for the coin.  The other die has the back (reverse) coin design on it.  

A proof coin is made with

a specially polished and treated die!

   By treating the die in a special way, the coins it produces have a different appearance.  Modern technology allows the high points on the coin design to be acid treated (on the die).  The background (field) design of the coin die is polished, resulting in a mirror-like look on the coin it strikes. This gives the finished coin a frosted look (frosting) on the raise parts of the design, with a mirror like finish on the background. This contrasting finish is often called "cameo".  (See picture above.) On some older coins a cameo appearance is quite rare. The attribute "CAM", when added to a coin's description, means cameo appearance. "DCAM" means deep cameo, and indicates the cameo appearance is strong and easy to observe.

Proof coins are struck twice, or more!

   Not only are proofs made using specially treated dies, each coin is struck two or more times by the coin die. By striking it more than once the metal is forced into all the crevices of the die, thereby giving a very fine detail to the image on the coin.  This fine detail does not appear on some non-proof coins. 

Grading proofs

   Today's grading of proofs is similar to the grades used for uncirculated coins.  The attribute "PR" or "PF" stands for "proof", and is used instead of the MS (mint state) to indicate a proof coin. Proofs (that are also un-circulated) will be graded PR 60 to PR70, with PR70 being rare or nonexistent in some cases.  Because a proof coin can be mishandled or receive wear by cleaning or handling, proof grades can extend below PR 60.  Example, a PR50 grade proof coin, is one that has had a touch of wear on the high points of the coin. Like uncirculated coins, proofs can experience toning, tarnish or darkening. 

Rarity and the Cost of Proofs

   Because of the extra effort, time, labor and production costs in making a proof coin, the respective government mints often sell them at higher prices.  In many instances the production of proof coins is limited.  The end result is that usually, but not always, a proof coin of the same date will be more expensive than a non-proof uncirculated. 

For most United States gold and silver coins, the proofs have the same amount of precious metal in them as non-proof uncirculated coins. 

Mint Marks on Coins

   Often U.S. proof and uncirculated coins will have a letter (mint mark) on the coin, indicating which United States government mint produced it.  Sometimes governments will make proof coins at a different mint than the regular (circulation strike) coins.  The US government has minted coins at these mints in the past: 

P - Philadelphia *

S  - San Francisco

W - West Point

D -  Denver

D - also used for Dahlonega GA mint on old gold coins **

CC - Carson City (old silver coins) **

C - Charlotte NC mint - on old gold coins **

O - New Orleans **

* Plain, with no mint mark, usually indicates it was made at the Philadelphia mint.

** Coins are no longer produced at these mints.

Copyright © 2003-2004 J. Lynn and www.Lynncoins.com

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