Grading Indian Head pennies is not an exact science where a precise method can be applied, and everyone comes out with the same result. But over the years, numismatists and coin grading services have agreed upon specific definitions, descriptions, and Sheldon’s numeric values that help all coin collectors describe their coins correctly (to a certain extent). Beginning in 1864 the nickel was removed from the composition and replaced with 95% copper and 5% tin and zinc. This new alloy made the metal softer and easier to strike. Since nickel was eliminated from the alloy, coins were now more susceptible to toning. Therefore, grades of mint state or uncirculated also take into account the color of the copper coin. The color of the coin is designated as red (RD), red/brown (RB) or brown (BN) and listed after the numerical grade. For example “MS63RB”. As mentioned earlier, some Indian Head pennies were difficult to strike up properly. If a coin was not fully struck using the proper amount of pressure in the coining press, the highest points on the coin’s design would be flat. This isn’t because they were worn off, it’s because the penny was not properly made. Coins like this can still be classified as uncirculated.
The Official American Numismatic Association Grading Standards of United States Coins Photograde: A Photographic Grading Encyclopedia for United States Coins Making the Grade: A Grading Guide to the Top 50 Most Widely Collected U.S. Coins Grading Coins by Photographs The Official Guide to Coin Grading and Counterfeit Detection