Coins of proof quality have no equal in sharpness or brilliance. These specialty made coins are so finely sculptured that extreme details are noticeable.
A proof coin’s exceptional detail combined with its aesthetic appeal make them extremely popular with collectors.
In terms of output, a proof is the absolute highest quality coin a mint can produce.
What, why and how these coins are made are just a few things we’ll discuss.
What exactly is a proof coin?
We glazed over the general description of proofs, but let’s get more specific. Foremost, proof coins are made for collectors, special occasions or other numismatic purposes. They are not coins intended for general circulation. Now, let’s get into some proof coin anatomy.
The anatomy of a proof coin…
The foreground or portrait area of a modern proof coin is often described as having a "cameo" effect. This effect is obtained by creating a special frosted, matte finish. Prior to technological advancements in the later 70’s, it wasn’t so common to see the full cameo effect, if there was one at all, on a proof.
It’s for this reason you’ll sometimes see descriptive designations of "CAM" or "DCAM" with certain proofs in addition to their official graded designation (described below).
CAM stands for cameo while DCAM stands for deep cameo. The latter, obviously, being the more attractive coin. (Note, sometimes you’ll see CA used instead of CAM and DC for DCAM.)
Mints of today can pretty much create a deep cameo coin at will and through the mintage cycle of a proof. In fact, another designation of "Ultra" cameo has been added to the marketing descriptive mix and is often used to describe the very best of today’s proof coins.
The background surface or field areas of proof coins are highly-polished, shiny and mirror-like. In fact, when you stand back and look at a proof, you’ll see your reflection on its surface.
When you look at any modern proof coin, you’ll notice the foreground and background areas sharply contrast. That’s intended. When you add in the bold, sharp details on a proof, the effect is quite spectacular.
What is a Reverse Proof coin?
New to coins is the "reverse proof". They’re manufactured exactly like other proofs with two exceptions. The finish techniques of the background and foreground are swapped. The portrait foreground isn’t frosted but instead mirror-like and the background surface isn’t shiny and mirror-like but instead frosted.
How is a proof coin made?
The Mint must use a special minting process to achieve the proof finish and overall look. The minting methods have actually improved through the years, resulting in superior proof finishes. Here’s that process as described by the United States Mint:
"Proof blanks are specially treated, hand-polished, and cleaned to ensure high-quality strikes. The blanks are then fed into presses fitted with specially polished dies and struck at least twice to ensure sharp, high relief. The coins are then carefully packaged to showcase and preserve their exceptional finish."
When breaking down the distinct parts of creating a proof, you can see a clearer picture of the process:
- Each is inspected and only the best are chosen
- Each go through special polishing and are cleaned with soft cloths
- After several uses, the dies are cleaned again
- They’re replaced frequently
Proof Blanks and Mint Press:
- Each are polished and cleaned with a soft cloths
- Each are hand fed into a coin press one at a time
- Each is struck at least twice by the press, providing high detail
- Higher pressure settings are used when pressing, also giving greater detail
- Much slower speed and care is taken
- Unique inspections for quality are performed
- The proofs are never touched by bare, human hands
- Each coin is sonically sealed in special coin holders/cases
How are proof coins handled and stored?
It’s important to realize that proof coins are not meant for general use or public circulation. They’re meant for coin collectors or numismatists. Because they’re uncirculated and designed that way, these coins by their very nature shouldn’t show signs of wear.
That means there will no handling or bag marks and few, if any, nick or other abrasions like you always see on every day pocket change.
Modern proof coins also come packaged within special holders for protection. It’s not the holders that are important but the fact that the proofs undergo special care at the Mint and are sonically sealed and inserted into the holders to help maintain their condition.
Although proof coins enjoy optimal care, handling and storage, that doesn’t mean they’ll always be free from toning, spotting or discoloration. In that, they are like any other coin and can suffer from exposure to air and dampness.
You may be wondering how coins that are sonically sealed within plastic cases or holders can experience discoloration. A sonic seal is unlike a vacuum seal. It doesn’t eliminate air from reaching the coin, which can cause oxidation and the resulting toning, spotting or other discoloration.
Why are proof coins made? What’s their history?
The concept of proof coins goes back centuries. From early on, specialized care, extra time, polished dies and other "proof-like" processes were used in what could only be described as a very basic quality assurance program.
The "prototype" coins created were studied for problems so any needed adjustments could be made prior to mass minting. The first batch of minted coins from these systems of checks were kept many times – almost like souvenirs.
It only made sense. These coins, after all, stood out in quality compared to any other. They were unique. And because they were unique, some were kept by employees while others were given to special Mint visitors, politicians, pioneering collectors who were wealthy and could buy or get special access to them and other "privileged folk".
Today these coins are generally referred to as "specimen" coins. That’s because no designation, standardized process or any other official program was in place, like there is in making present day proof coins.
It’s not surprising that eventually the popularity of these specimens spread and the demand for them increased.
Eventually, the mint started to specifically make coins for the intent of appeasing collectors. Organization, structure and uniformed manufacturing processes resulted. The birth of proof coins came into being.
Yearly mintage numbers of proofs
The real explosion in demand for proofs occurred in the early 1900’s. Mintage numbers went up from just a few thousand in the 1930’s to tens of thousands and then eventually hundreds of thousands in the 1950’s.
Today, many countries make proof coins and sets for collectors. The U.S. Mint produces millions of different proof coins every single year.
How proof coins are graded
First, it’s important to note that the term "proof" does not refer to the grade or condition of a coin. It only describes how a coin is manufactured. That can be somewhat confusing for some simply since a proof coin implies, because of the way they’re made, a certain "near perfection" distinction.
Proofs are classified with a "PF" designation. (It’s not uncommon to see "PR" in place of "PF". They both mean "proof".) The numerical level indicators are similar to grades of other coins. And like them, can range from 70 down to 1. Here are a few of the popular called grades:
- PF-70 indicates perfection and the best coin strike
- PF-65 is sometimes called "Gem Proof". A coin graded PF-65 may have a few noticeable hairline scratches. The strike of the coin will be above average.
- PF-63, which is sometimes referred to as "Choice Proof", will have several hairline marks. The strike of the coin may not be "full".
- PF-60 is the lowest grade on the "main" proof totem pole. At this grade, the coin will have many marks, the strike of the coin may not be "full", and the coin is always less appealing to the eye.
Naturally, there are cases where a proof coin can get placed into circulation, cleaned or otherwise mishandled. When this happens, the proof coin will still have the "PF" designation but with a lower numerical value.
That is, unless the coin is so worn that it’s impossible to tell it was ever a proof. In those instances, it’ll get graded as circulated and with their designations.
Although, PF-70 was once considered rare to the point of nonexistent, technological improvements at the U.S. Mint has changed the landscape significantly in recent years. PF-70 coins command huge desirability and premiums in price, but they’re much more common compared to past years.
The cost of proof coins
Just like other coins, the price scale of a proof coin has many factors. However, generally speaking, you’ll often notice that proof coins are more expensive than other uncirculated coins made for collectors and they’re always worth more than business strike or circulated coins.
That’s to be expected considering they’re made specifically for collectors. They usually have lower mintage rates, and more time and effort is needed to produce them.
They do indeed cost more to purchase originally from the Mint as well. As an example, the price point to purchase the 2007 United States Mint Proof Set directly from the Mint was $26.95, plus shipping and handling. The 14 coins within the set include:
- Lincoln one-cent coin
- Jefferson 5-cent coin
- Roosevelt dime
- Montana state quarter
- Washington state quarter
- Idaho state quarter
- Wyoming state quarter
- Utah state quarter
- Kennedy half-dollar
- Golden Sacagawea Dollar
- Washington $1 Coin
- Adams $1 Coin
- Jefferson $1 Coin
- Madison $1 Coin
Compared to the everyday business strike versions of these coins, that is a mark-up of $20. (Of course, the proof sets do contain the protective holders and packaging, which adds to cost.)
Aside from the unique beauty of proofs, coin collectors always love when their after-market values improve over time. However, history has shown fluctuation here. At times, you can purchase some proof sets at less than their original cost.
But… it would be unfair to stereotype proofs. The rare proof coins do command huge premiums. And many proof coins and sets – after a very short time – have doubled, tripled or more in price.
Mint facilities and locations that make proofs
The United States Mint was created by Congress on April 2, 1792, and placed under the Department of State’s control. Under the Coinage Act of 1873, the Mint became part of the Treasury Department and in 1981 it was placed directly under the Treasurer of the United States.
The U.S. Mint is not one single "place" but rather an institution. Over the years the responsibilities of the Mint have shifted but their main purposes has always been to produce U.S. coinage. Today, they do so through several Mint facilities.
And because of all the extras involved in making proof coins (labor, time, effort, etc.), not all U.S. Mint facilities produce them. There are currently four locations where coins are made:
- San Francisco
- West Point
If you look at the coins you receive in daily change, you’ll notice they have small letter "mint marks". These letters actually indicate which Mint facility produced the coin – "P" for Philadelphia, "D" for Denver, "S" for San Francisco and "W" for West Point.
Modern proof coins are made only in the San Francisco and West Point facilities. West Point is actually responsible for minting proof and commemorative coins that contain bullion, like the American Eagle and American Buffalo coins.