If you’re interested in identifying a doubled die coin, particularly a penny, here’s how to distinguish it from other forms of doubling:
- A doubled die error occurs during the die manufacturing process, where the die itself is flawed with a doubled image of the design elements.
- This happens because the coin hub, which is used to create the die, is misaligned or shifted during the hubbing process, imprinting the design more than once in slightly different positions.
- As a result, the doubled image appears on every coin struck by that faulty die.
- Doubled Text and Numbers: Examine the date, motto (“IN GOD WE TRUST”), and other inscriptions like “LIBERTY” and “E PLURIBUS UNUM”. You’ll see a clear, noticeable doubling effect, like a distinct shadow or overlapping image.
- Sharp Edges: The doubled areas on a genuine doubled die coin should have sharp, distinct edges, unlike the flat, smeared appearance of mechanical doubling.
- Full Doubling: In a true doubled die, both the primary and doubled design elements are approximately the same height from the flat surface of the coin, according to Dave W. Coins.
- In many cases, a magnifying glass or loupe will be necessary to clearly observe the subtle doubling and sharp edges.
- You may consider using a digital coin microscope for even greater detail, according to James A. Chambers.
- Machine Doubling (Strike Doubling): This occurs when the die shifts slightly during the striking process. The doubling will appear flat and shelf-like, lacking the distinct separation of a true doubled die, according to The Lincoln Cent Resource. It is not considered a valuable error.
- Double Struck Coins: These coins have been struck twice by the coining press, causing the initial design to be flattened or obliterated. Double struck coins often feature a fainter, secondary strike on both sides, which is distinct from the doubling of a doubled die.
- Always compare suspected doubled die coins with images of genuine examples from reliable sources like NGC or PCGS.
- Beware of blurred or slanted details, which can indicate a counterfeit.
- Authentic double die coins, like all other genuine coins, will also have a specific weight and metal composition.
- When in doubt, consult a reputable coin dealer or numismatist for expert authentication, according to Endeavor Metals.
By understanding the key characteristics of doubled dies and using the appropriate tools, you can confidently identify these valuable and interesting error coins.
Can any coin be a double die?
All U.S. coins made for circulation are only struck once unless there is a mishap in the coining press. Even then, the resulting error coins will NOT be doubled dies.
How rare is a double die penny?
Roughly 20,000–24,000 of the pennies were introduced into circulation after the minting error. The 1955 doubled die is one of the most famous die varieties in US coinage. Very few exist today in totally mint condition, as almost all were discovered while in circulation.