What Are Error Coins and Are They Valuable?

Akin to a modern-day treasure hunt, searching for valuable error coins is a fun and potentially lucrative side of coin collecting. It’s possible to run into errors in the wild—there’s a reason many coin collectors will instinctively examine their pocket change before spending it!

Unlike most low-population coins that are valued for their scarcity, condition, and market demand, these odd coins are coveted because they’re defective, and thus extremely rare. At some point in the minting process, a mistake was made, resulting in the finished coin being physically flawed.

As you might expect, minting blunders are extremely uncommon, but an error coin batch will slip through the cracks from time to time. Minting machinery is operated by humans, after all, so it’s only natural that accidents are bound to happen once in a while

There are many different types of errors that can occur throughout the minting process. In this guide, we’re going to explain how minting mistakes occur; we’ll also highlight the most well-known and desired examples to watch for. Let’s get started!

Types of Minting Errors

The American Numismatic Association separates minting errors into three categories: planchet errors, die errors, and striking errors. Each category includes numerous subcategories of specific mistakes that lead to the creation of an error coin. 

The more uncommon the type of error, the more valuable error coins will be. The defective coin’s value is also determined by its condition—post-mint damage is not desirable—as well as the overall popularity of the coin series.

Here’s an overview of each minting error.

Planchet Errors‍

1. Blank Planchets

Planchets are blank metal disks that eventually become coins. On rare occasions, they enter circulation without being struck.

2. Clipped Planchets

When planchets aren’t fed into the blanking machine properly, they may be clipped.

3. Split Planchets

When grease, gas, or various debris becomes trapped under the planchet, the lamination can be compromised, causing the coin to split, peel, or flake.

4. Improper Thicknesses

An error coin can occur when a planchet is too light or heavy.

5. Lamination Flaws

Impure or compromised metals can cause lamination flaws, such as uneven surfaces, peeling, splitting, or discoloration.

6. Cladding Flaws

Some modern coins are made with clads, which are layers of different metals. The layers can separate, fold, or peel away from each other.

Die Errors

Dies imprint the images on coins. Die-related errors can be caused by defective dies, incorrectly installed dies, or degradation of dies over time.

1. Fundamental Die-Setting Errors

When a die isn’t set in the proper position, an error coin batch may occur.

2. Missing Design Elements

If the die has an error during the striking process, a coin may be missing a feature, such as a mintmark or date, resulting in potentially valuable error coins.

3. Die Defects

If a die chips, cracks, or breaks during striking, they may cause the coin to have raised, jagged lines on the surface.

4. Double-Dies

When a coin receives an unintended second impression due to a faulty die, it may have a doubling or overlapping effect or even a completely different second design imprinted over the original. These are called double-dies.

5. Die Clashes

If two dies clash against each other because a planchet wasn’t between them, the dies can be damaged and cause distorted images on the subsequent coins.

6. Punching Errors

An error coin may be caused when a coin requires that its perimeter’s design is punched separately from the main image’s die.

7. Overmintmarks and Overdates

Mints used to recycle dies until they broke, replacing the mintmark and date at the beginning of each year. In some cases, the previous year’s mintmark or date was still visible.

8. Mules

A mule coin occurs when a coin is struck with two unrelated dies. The coin may have two unique denominations, for example.

9. Trails

Trails are coins with lines caused by coin movement during the single pressing minting process.

Striking Errors

An error coin can be caused by a problem during the striking process, rather than due to issues related to the blanks or dies. These are some of the most desirable and valuable error coins.

1. Strike-Throughs

If an object becomes trapped between the blank and die, the outline of the object can be left behind on the coin’s surface.

2.  Broadstrikes

Broadstrikes are coins with plain edges caused by a malfunction with the collar die.

3. Edge Strikes

If a coin bounces during the striking process, it may get struck on the edge, causing it to bend or even fold flat over itself.

4. Multiple Strikes

Often confused with a double die error coin, multiple strikes occur when the die strikes the coin more than once, resulting in multiple images.

5. Off-Center Strikes

If a coin isn’t lined up properly, it may have the image struck off center.

6. Uni-Face Coins

Uni-face coins occur when two coins are stacked on top of each other and then struck, resulting in one coin with only a reverse image and the other with only an obverse image.

7. Brockage

If a struck coin doesn’t eject properly, a new planchet can get stuck between the coin and the die. This can cause a mirror image from the previous coin to become struck on the new blank, which is called brockage. 

8. Die Caps

If a brockage error coin isn’t removed from its stuck position, the continuous striking may cause the coin to become warped into a shape that resembles a bottle cap.

9. Wrong Planchet Strikes

If the planchet for one type of coin is fed into a stamping press for a different type of coin, a wrong-planchet error may occur.

11. Rim and Edge Errors

Collars are used to prevent planchets from spreading or flattening when struck. If the collars are misaligned or deteriorated, they may cause errors on the rims or edges of coins.

Valuable Error Coins 

While an individual error coin is certainly a rare treasure, a mated pair (or set) that comes from the same error batch is especially valuable. For example, you could have the die cap coin that caused brockage and the coin that has the brockage.

Here are some of the most well-known American coins that have been circulated with errors.

• 2007 Presidential dollars missing edge lettering
• 2004-D Wisconsin extra leaf quarters
• 1995 doubled die obverse cent
• 1984 doubled ear cent
• 1983 doubled die reverse cent
• 1982 No P dime
• 1972 doubled die obverse cent
• 1970-S doubled die obverse cent with a small or large date
• 1958 handsome mule Franklin half dollar
• 1955 doubled die obverse cent
• 1944 steel cent
• 1943 copper cent
• 1942/1-D Mercury dime
• 1942/1 Mercury dime
• 1937-D 3-legged Buffalo nickel
• 1918/7-S Standing Liberty quarter
• 1918/7 Buffalo nickel

Explore Error Coins and Other Rare Numismatics

Endeavor Metals is a Tier 1 US Mint precious metals dealer, as well as trusted source for elusive rare coins. We stock a wide range of low-population gold, silver, platinum, and palladium numismatics, including some very unique coins with minting errors.

If you have any questions, or if you need some help tracking down specific valuable error coins, contact us for a free consultation with a qualified numismatist. 

Each and every error coin is a one-of-a-kind collector’s piece with significant room to grow in value. Add historical significance and prestige to your coin collection. Invest in an error coin today.