In American numismatics, there are many instances where coins are common in one grade but surprisingly scarce in another. That is, a coin might be readily available in, say, MS 62 but virtually impossible to find in MS 64. Why would minute differences in grade turn a common coin into a major rarity? There are numerous reasons for this phenomenon—and this article will describe some of the contributing factors.

Some coins, simply put, were not well-made. For instance, half eagles from the 1880s are usually seen with muted luster, which ultimately limits their grade. 1881 and 1882 half eagles, while very common in Uncirculated, are usually drab-looking coins that qualify as MS 61 or MS 62. By comparison, later dates are more likely to be seen with flashy, vibrant luster. A date like 1901-S, which often exhibits strong “cartwheel” luster, is more likely to be seen in the MS 63 to MS 65 range.

In the silver dollar series, a similar situation exists. In lower uncirculated grades (MS 61-MS 63), dates like 1883-O, 1884-O and 1885-O are the most available. In high grades (MS 65 – MS 68) the most common issues are 1879-S, 1880-S and 1881-S. Notice a pattern? The New Orleans Mint was notorious for coins with flat strikes; as a result these “O-Mint” coins rarely qualify for higher grades. The San Francisco issues, meanwhile, are superbly made with sharp strikes and booming luster.

Another factor is how the coins were stored. Some coins entered circulation immediately; very few original rolls, bank bags or other protected hoards existed. These coins are almost always seen with extensive wear and circulation. Coins that were stashed away in vaults or removed from circulation can be found in higher grades with ease. An example is first years of issue; these new releases were often saved by Americans as keepsakes (and thus are much more likely to exist in lofty grades).

One extreme example of coins being removed from circulation: shipwrecks. Several vessels from the 1850s and 1860s sank with large quantities of gold coins on board, only to be recovered by explorers in the 20th century. As a result certain “shipwreck dates” are more likely to be seen in pristine Uncirculated condition than lower grades. For instance, a tremendous quantity of 1857-S $20 pieces were found in the SS Central America shipwreck. As a result, this date is actually more available in MS 64 than XF 40!