A "grade" is a shorthand devised by numismatists to indicate the appearance of a coin. In other words, if one collector tells another that he has an About Uncirculated-50 Charlotte half eagle, both collectors should have an expectation of what the coin should look like, even if one has never seen it, due to the implications of its grade. For many years, there were a relatively small number of adjectival grades. Grading became more "scientific" in the 1940's when the numerical grading scale was invented by Dr. William Sheldon. This scale, which ranged from 1 to 70, was originally devised to ascertain values of 1793-1814 Large Cents by ascribing a basal value to each variety and multiplying this value by the grade in order to determine a price.
The Sheldon grading scale is now used by most numismatists. Newcomers tend to complain that there are "too many grades" but experienced graders appreciate that there can be a huge range in quality between specific ranges.
To better understand coin grading, it is important to study the major components of grade. When I grade a coin, I employ five important individual components which, when taken into consideration as a whole, help me determine my opinion of a coin's grade. These individual components are strike, surface preservation, luster, coloration and eye appeal.
Strike: The strike of a coin refers to the process of stamping a design onto a planchet or a blank. A coin can have either a strong or a weak strike. Much of this depends on a coin's design. As an example, certain designs (such as the Type II gold dollar) have the highest relief element on the obverse directly aligned with the highest relief element on the reverse. This means that weakly struck coins are the rule for these designs. Other designs (such as the Indian Head quarter eagle) may be found with sharp strikes on certain issues and weak strikes on others.
Generally speaking, strike is not a major element in determining the grade of a coin unless it is in a series in which value is related to strike. In a series such as Mercury Dimes, where a PCGS MS-66 1945 dime is worth $15 and the same coin with a full strike (designated in this series as "Full Bands") is worth $7,500, strike is a huge element. In all but a handful of circumstances, strike does not play a critical role in determining the value or United States gold coins.
Surface Preservation: The number of marks on a coin and their placement are important factors in determining grade. There is no set formula that says "X" number of marks on a coin's surface means that it grades "Y." But there are some fairly normalized standards in terms of the importance of an abrasion's location.
If a very nice coin has a deep mark that it is well-hidden on the reverse, it tends not to be severely penalized. But if the exact same mark was located in a prominent focal point on the obverse (the cheek on a Liberty Head double eagle, as an example) it would be penalized considerably more.
Coins that have a very open, uncluttered design tend to show marks more obviously than those with tight, compact designs. For this reason, the intensity of the marks on a Liberty double eagle play a greater role in determining grade than on a Type Three gold dollar.
Certain types of coins are known for showing greater concentrations of marks than others. As an example, the quarter eagles struck from 1821 to 1834 did not see ready circulation. They tend to have reasonably clean surfaces. Indian Head quarter eagles, on the other hand, saw a greater degree of circulation. It is much harder to find examples that do not have the marks, scratches and scuffmarks associated with circulation and/or poor handling.
On United States gold coins, surface preservation is very important in determining grade.
Luster: Depending on the design, mint of origin and the metal used a coin may have a variety of surface textures. These include satiny, frosty, semi-prooflike and prooflike. When analyzing the surface of a coin in regards to grade, there are two things to look for: the amount of the original surface (or "skin") that is intact and the amount (and location) of marks.
There is really not one type of surface that is "better" than another. In certain series, such as Morgan dollars, premiums are paid for pieces with mirror-like surfaces. In most other series, prooflike coins may be regarded as interesting but not necessarily worth a premium.
On 19th century United States gold coins, I am most fond of a frosty texture. This texture can be found on issues from all mints but it is most closely associated with Philadelphia and San Francisco.
Luster is especially important in determining if a coin is Uncirculated or not. A Mint State coin is, technically, free of wear and should not have major breaks in the luster. However, this is often not the case for coins graded Mint State-60 and Mint State-61. These coins will typically show breaks in the luster; perhaps as a result of a light cleaning or "rub" that occurs from improper storage in an album. A coin that is not Uncirculated will show a greater amount of breaks in the luster and, obviously, a smaller amount of luster.
Luster is another very important component in determining the grade of a United States gold coin.
Coloration: Color is the most subjective factor in determining grade. A coin is either well struck or it's not well struck; this is not open to debate. But a gold coin that shows deep green-gold color may be attractive to one viewer and unattractive to another. In my opinion, attractive original coloration greatly enhances the appearance of a coin.
Gold is a relatively inert metal and not subject to as much variance in coloration as silver or copper. However, a wide range of colors may be present on gold coins.
Coins from the Charlotte and Dahlonega mints have very distinctive coloration as a result of the amount of silver or copper that was part of the gold found in these sources. Philadelphia and San Francisco pieces have much different coloration.
The majority of United States gold coins have been cleaned or dipped at one time. As a result, they no longer display original coloration. As collectors become more savvy, they are often attracted to coins with pleasing natural color. In many series, it is almost impossible to find original pieces. In the near future, it is likely that totally original pieces will be accorded a strong premium over "typical" examples.
Color is not as important a factor in determining the grade of a gold coin as it is on a silver or copper coin.
Eye Appeal: The four individual components listed above, when combined, form an all-encompassing component that is called "eye appeal." This is a fairly self-explanatory term. A coin that has good eye appeal may be very strong in one area (excellent luster, for example) and good in another (nice but not great color). If a coin is negative in one area (very heavy marks, for example) but acceptable in all others, it is still likely to be noted as having below-average eye appeal.
The concept of eye appeal seems subjective but it is really not. Most sophisticated coin buyers will agree that a certain coin has good or bad eye appeal. But it does require a certain level of knowledge to make this determination.
There are some specific dates or types that almost always come with poor eye appeal and a coin that is somewhat attractive may be considered to have good eye appeal "for the date." As an example, all known 1870-CC double eagles have heavily abraded surfaces. A coin that has typical marks but none located in very prime focal points may be looked at as having good eye appeal for the issue. But if this were any other date, the exact same coin might be regarded as having poor eye appeal. It takes in-depth knowledge of a specific series to make this determination.
Grading is an important subject and this article could easily have been two or three times longer. If you have any questions regarding the five components of coin grading, please feel free to email me at email@example.com and I will do my best to answer them.