4 Collectible Coins That Are Difficult to Grade

Grading coins is a difficult skill to learn. You will see that there are some coins that are easy to grade and other coins that are more difficult. Remember, grading standards are agreed upon by most coin dealers and coin collectors. However, the application and interpretation of those standards can vary greatly between collectors and dealers.

A beginning coin collector may get confused when they start learning the skill of coin grading. This is usually caused by slight nuances in a particular series of coins that take a different set of grading skills to apply. Additionally, there are a variety of designs that lend themselves to be more difficult-to-grade than others. Here are four particularly tough coin types to grade.

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    Copper Coins Minted Before 1815

    Copper Coins Minted Before 1815
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    Copper coins that were minted before 1815 (half cents and large cents) are particularly difficult to grade. Most of this is because of the poor planchet quality that the coins were made from. At this time in American history, the United States was a young and growing country. Most copper was imported from England and other foreign countries. The United States Mint had very little control over the quality of the planchets they were receiving.

    Problems included: Laminations, impurities that caused color changes, poor quality planchets, clipped planchets and porous ones. Additionally, the minting technology employed by The United States Mint was not state-of-the-art. This lead to off-center strikes and improperly aligned dies. These two problems in particular, led to a loss of detail on the finished coin.

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    Silver Coins Struck before 1809

    Silver Coins Struck before 1809
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    Silver coins struck before 1809 are also troublesome to grade. In addition to the minting problems mentioned above, half dollars and silver dollars are particularly difficult. First of all, these large coins were generally difficult to strike accurately using the archaic minting processes of the time.

    If the dies were not properly aligned in the coining press, certain parts of the coin would not strike up properly. Remember, the highest points on the design are the lowest points on the die. These areas will be the last to fill during the striking of a coin. Therefore, it may look like the missing design is due to the coin being in circulation. However, upon close inspection you will see original mint luster throughout all the areas of the coins that were properly struck. This may cause confusion to some coin collectors because the coin will look worn but still receive an uncirculated grade.

    In order to ensure quality, individual planchets were weighed by mint workers before being sent to the coining press. If the planchets were found to be overweight, the mint worker would take a file and scrape off some silver until the planchet was within tolerance. Then, if the coining press did not strike the coin hard enough, the adjustment marks would still be visible on the finished coin.

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    Pre-1925 Standing Liberty Quarters

    1916 Standing Liberty quarter graded G-6 by PCGS
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    In 1916, when the Standing Liberty quarter was first introduced, the date on the obverse was raised above the rim. This turned out to be the highest point on the coin and also lent itself to wearing away prematurely. If the date is not discernible, the coin cannot be graded.

    In order to solve this problem, The United States Mint in 1925 began producing Standing Liberty quarters with the date sunken below the rim. Now this design element moved from the highest point on the coin to one of the lowest points. Most of the remaining design elements remained unchanged and experienced wear in the same way coins made before 1925.

    This leads to some confusion because in 1925, the date was recessed below the rim. Some coin collectors do not understand how a coin minted after 1925 can have more details than a coin minted before 1925 and still receive a lower grade. Remember, in order to meet the minimum qualifications for a grade of "Good," the date and the coin must be discernible.

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    Indian Quarter Eagles and Half Eagles

    1909-O Indian Head Half Eagle Five Dollar Gold Coin
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    Bella Lyon Pratt designed the Indian Head Quarter Eagle ($2.50) and Half Eagle ($5.00) gold coins. What made this coin revolutionary was that the design was sunken below the field of the coin. Some people improperly call this incuse but it is actually considered a “sunken relief” design.

    Therefore the highest point on the coin is the field and not the design. Many coin collectors are used to looking at the highest point on the design to determine the grade of the coin. These two coin types go against this common coin grading rule.

    A skilled coin grader will look at the field of this coin in order to determine if it has been circulated or not. The first thing you must look for is original mint luster throughout the field on the coin. The mint luster may be subdued or impaired slightly because it was damaged during the manufacturing process or handling at a bank. This impaired mint luster does not mean it is now a circulated coin. However, if the mint luster is lacking in the field altogether and it is covered by nicks, scrapes, hairlines and small scratches, this definitely means the coin has been circulated.