Sheldon coin grading scale

The American Numismatic Association based its Official ANA Grading Standards in large part on the Sheldon scale.

[4][5] Note: Some early American coin varieties are almost always found to be weakly struck in places.

Coins in the lower grade range (60-63), are usually unworn, and may suffer from weak striking, bag marks and other defects that make them less attractive to the collector.

Some Mint State early coins appear to be circulated due to weak strikes, die cracks, planchet problems, or metal quality.

There are a few United States coins for which no mint state specimens exist,[10][11] such as the 1792 silver dime, and the 1802 Draped Bust (Heraldic Eagle reverse) silver half dime.

Along these lines, some numismatists argue that an unscrupulous subset of coin dealers mislead customers by using adjectival grades without defining their terms.

Photograph of 1793 Flowing Hair (chain) Cent
Example of an Early American Cent - the coins that inspired Sheldon to create a more precise grading scale. (Courtesy of the National Numismatic Collection , National Museum of American History [photograph by Jaclyn Nash].)
A selection of three Walking Liberty half dollars of various coin grades and years, ranging from AG (About Good) to AU (Almost Uncirculated).
A Walking Liberty half dollar in MS (Mint State) condition, graded MS66.