How to Identify and Collect Coin Die Varieties and Errors

A Collector’s Guide to Die Varieties and Error Coins

For many, a coin is just a coin. But for the keen-eyed collector, some coins tell a fascinating story of when things went slightly wrong. These aren’t damaged coins; they are unique pieces that left the mint with a flaw, making them rare, valuable, and highly sought after.

Welcome to the world of error coins and die varieties.

This guide will walk you through the basics of this exciting niche in numismatics. You will learn how to identify error coins, understand the difference between a variety and a true error, and discover what makes these coins a thrilling addition to any collection.

What Are Error Coins and Die Varieties?

First, it’s important to understand the distinction between these two related terms.

• Error Coin: An error coin is a coin that has a mistake made during the manufacturing process (the striking of the coin). These are typically one-off, accidental mistakes.
• Die Variety: A die variety is a coin that has a mistake originating from the die itself (the stamp used to strike the coin). Because the die is flawed, this mistake will be passed on to every coin it strikes, creating a series of identical “error” coins.

In short, die varieties are a specific, repeatable type of error. To the U.S. Mint, they are all mistakes, but to collectors, they are treasures.

How to Identify Common Die Varieties

Die varieties are some of the most famous and sought-after types of error coins. Learning to spot them requires a keen eye and often a magnifying glass. Here are the most common types.

The Doubled Die

Perhaps the most famous variety, a doubled die occurs when the hub impresses the design onto the die more than once, creating a slightly offset, doubled image. This is not the same as a coin being struck twice; the doubling is part of the die itself.

• How to Spot It: Look for a clear doubling of letters, numbers (especially the date), or parts of the main design. The 1955 Doubled Die Lincoln Cent is the most famous example of this.

Repunched Mint Mark (RPM)

Before 1990, mint marks were punched into each working die by hand. If the first punch was misplaced or crooked, it would be corrected with a second punch, often leaving traces of the original mark visible.

• How to Spot It: Look for a faint secondary mint mark (“S,” “D,” or “P”) underneath or next to the primary one.

Over Mint Mark (OMM)

Similar to an RPM, an OMM occurs when a die is sent from one mint to another and the new mint mark is punched over the old one. The most famous example is the 1944-D/S Lincoln Cent, where a “D” was punched over an “S.”

Understanding Major Minting Error Coins

Unlike die varieties, these errors are typically one-of-a-kind mistakes made during the minting process itself. Learning how to identify error coins like these can lead to incredible finds.

Off-Center Strike

This is a dramatic and popular error. It happens when the coin blank (planchet) is not seated correctly when it is struck by the dies. The resulting coin will have a portion of its design missing, with a crescent of blank space.

• How to Spot It: This is a visual error. The more off-center the strike is, and the more of the date that is still visible, the more valuable the coin tends to be.

Broadstrike

A broadstrike occurs when a coin is struck outside of the retaining collar that forms its rim. This results in a coin that is much wider and thinner than a normal coin, with a plain, flat edge.

Clipped Planchet

This error happens at the very beginning of the process when the blank coin discs are being punched from a large metal sheet. If the punch overlaps the previous hole, it creates a “clipped” plan-chet with a curved piece missing.

Tips for Collecting Error Coins

Getting started with collecting error coins is an exciting journey. Here are a few tips to guide you:

1. Start with Your Pocket Change: You don’t need to spend a fortune. Scrutinize every coin you get. Many valuable errors have been found in everyday circulation.
2. Get the Right Tools: A good quality 5x or 10x magnifying glass (a jeweler’s loupe) is essential. A coin book or guide, like the “Cherrypickers’ Guide to Rare Die Varieties,” is also invaluable.
3. Buy from Reputable Dealers: When you’re ready to purchase specific error coins, always buy from a trusted, knowledgeable dealer. This ensures authenticity and fair pricing.
4. Know the Difference: Learn to distinguish true minting errors from post-mint damage (PMD). Scratches, dents, or alterations that happen after a coin leaves the mint do not add value.

By understanding what to look for, you can turn a simple hobby into a thrilling treasure hunt. Happy collecting!