Here are two timeless questions in numismatics: “Is my coin an error?” and, “Is my coin a variety?” Hopefully this article will clearly answer both of these questions.
Errors
An error is a mistake stemming from the method of manufacturing and can be insignificant or massive. The significance of the error can be judged on the specific mint that produced it and the tolerances that mint has for manufacturing defects, this is called “mint tolerance.” Errors can occur at any time during manufacturing the coin. These mistakes can be anything from an inconsistent mixture of the metal that the coin is made from, to planchet-production issues, to striking, and even thereafter. Most errors are unique to that particular coin. If the metal is off, made on a wrong or clipped planchet, and/or struck incorrectly, usually this only occurs on one or perhaps a few pieces. Collectors of error coins judge the significance and the market value of these pieces, which means some errors can be considered detrimental and of less value as compared to a non-error coin, while others are considered significant and bring fortunes to those who discover and sell them.
Varieties
A variety is often something that has to do with the die or dies that were used to produce the coins. The die that strikes or casts a coin holds the design that will be transferred to the coinage it produces. Any variance in design from one die to another causing a difference large or small on each coin struck from that die as opposed to another is a variety. These varieties can be significant or insignificant, again depending on mint tolerance. When dies were handmade, each one became different and often easily identifiable. Yet, any mint using handmade dies allows for significant differences from coin to coin, thus not considering it anything outside of their judgement of tolerance. When machine-made dies came into effect the degree of acceptable variance dropped and more consistent coinage was the goal. Die differences such as repunching, recutting, doubled dies, and other distinguishing factors became collectible varieties to the generic coinage for those who choose to collect them. These varieties will repeat on each coin struck by the die that holds this inconsistency, thus making them a variety.
Below are three examples of a variety showing up on multiple similar examples. All three pieces have a strong doubled die obverse on the patch. Notice how this feature repeats on each coin. This is a variety.
The In-between
1798 Cents S-148 all from the same dies, but in different states, showing an unbroken die, one die break cud, and two die break cuds – all the same dies.
Some coins can be both errors and varieties. This has to do with the nature of the coin’s manufacturing and quantities of pieces produced. Die breaks, mules, and even some off-metal strikes are both errors and varieties by numismatic definitions. For instance, die-breaks are caused when the die starts to crack and break away. These are progressive error-varieties that change as more and more of the die breaks away. And, since most pieces struck by these failed or failing dies would never be considered acceptable by most mints, they are considered both an error and a variety as they repeat on multiple coins, some assigned by reference numbers. Mules are errors from which two dies never designed to be used together are; they are considered both errors and varieties. Some off-metal pieces like the transitional 1943 Bronze and 1944 Steel Lincoln Cents are so famous that even though they are errors they are considered by some necessary varieties for their complete Lincoln Cent set. Following a long hiatus of implementing this process on coinage, the United States reintroduced edge inscriptions in 2007 to dollar coins, and this edge lettering was added in a separate step from striking the obverse and reverse. Entire bins of struck coins never had their edge lettering added in error and were released to circulation without edge lettering. These are errors but were produced in such abundance that they are considered a variety to the series.
Non-Errors & Varieties
This again comes down to what mint tolerance for the particular coin is. Many coins will exhibit microscopic doubling, the most minor repunching, die clashing, die polishing, and other die-identifiable aspects that the most mints have accepted as tolerable since it can only be found with high-power magnification or microscopes. The same can be said for tiny metal planchet flaws, laminations, struck-though pieces, and many other types of minor production flaws. These are by most collector standards insignificant, but some numismatists have written entire catalogs on these subjects. Damage and post-mint alterations are also not errors or varieties. Once the coin leaves the mint it can be damaged and altered, and these are not errors or varieties, but some will try to pass them off as such.
The best thing for one who is interested in errors, varieties, or any other areas of numismatics to do is to learn about the topic before diving in. By doing so, you can ascertain when common anomalies and insignificance are being promoted as rare and grand, while having an overall better understanding of what is considered collectible. There are many wonderful and significant affordable errors and varieties giving even collectors on limited budgets the opportunity to put together nice collections.