1978 Penny Error: Clipped Planchet Coins
This 1978 D penny is a curved clip mint error coin, a type of numismatic error that occurs during the production of coins.

In other words, this 1978-D penny error refers to a clipped planchet, or portion of the coin’s circumference being absent. This is due to a misalignment during the blanking or cutting process.
Furthermore, the blanking process involves cutting round metal discs, called planchets from large sheets of metal. Occasionally, the cutting machine may malfunction or experience misalignment. This results in irregularly shaped planchets. Moreover, the irregularly shaped planchet used to strike this 1978 penny, created a clipped planchet coin error.

Note the Crescent-shaped Indention
Essentially, a curved clip mint error is named because a missing portion of the planchet creates a curved or crescent-shaped indentation. The location and size of the curved clip can vary, but typically affects a small segment of the coin’s circumference, as shown above.
Curved Clip Mint Error Coin Value
The value of a curved clip error coin may vary. Moreover, it depends on several factors, such as the severity of the clip, the rarity of the coin, and the demand among collectors. Additionally, the more pronounced and larger the curved clip, the more desirable the error coin becomes. Had this 1978d penny been in flawless condition, it might’ve been a penny worth thousands.

To determine the specific worth of a curved clip mint error coin like this 1978 Lincoln cent, have it authenticated and appraised by a professional coin grading service or a reputable numismatist. For a small fee, they’ll assess the coin’s condition, rarity, and market demand to provide a valuation estimate.

Note the Blakesley Effect
The Blakesley Effect refers to a specific type of error that can occur during the minting process of coins. It’s named after a man named Blakesley, who first described this phenomenon.
The Blakesley Effect specifically refers to the raised rim formed along the clipped edge of a coin. A coin struck with insufficient force or misalignment, displaces the metal pushing it upward. This causes the formation of a ridge or rim along the clipped area and a flattened area opposite the clip.

Coin collectors find these errors intriguing due to their unique appearance and the circumstances during minting process. List your own mint error discoveries on eBay by observing how others have listed theirs.

If you’ve found a clipped error coin you think is valuable, then consult with experts in the field to get an accurate assessment of its worth. Online coin groups such as coinauctionshelp.com are extremely valuable resources to be aware of.
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