A coin planchet is a metal, rounded disk containing the blended alloys that makeup a coin.
When I think of a planchet, I’m reminded of medieval movies where a smith pulls a long piece of metal from a fiery pit and then pounds away on it, forming a sword. Prior to the final strikings, the raw metal is somewhat similar to a coin planchet – it has the proper metallic content and general shape but it’s clearly just a piece of unfinished metal.
In the case of coins, the metal planchet has a rounded shape and raised rim. (Before the rim is raised, the metal disc is usually referred to as a “blank”.) Planchets are struck and pressed at US Mints, creating the final coin image.
If a coin planchet is just a piece of unfinished metal, how can it be worth anything? Certainly there’s inherent value to the metal itself. Generally speaking, however, unless it’s a larger planchet containing a high percentage of platinum, gold or silver, very little value will be due to its content. Instead, the value comes from the fact that the coin planchet was involved in the US Minting process. 
More notably, the planchet was an ERROR that escaped US Mint quality assurance eyes and made it to public circulation. There’s an attraction with many coin collectors for this type of historical error or uniqueness.
What are coin planchet errors worth? Coin planchet errors can vary greatly in price. Much depends on the type, its date, error type, uniqueness, and, perhaps most importantly, its rarity. Some popular planchet error types include:
- A completely blank planchet
- An off centered striking – the coin press hits the planchet partially causing, you guessed it, an off centered coin image
- Doubler striking – the coin planchet is struck at least twice resulting in overlapping coin images
- Clipped planchets – there was an error in the original planchet getting cut to its correct size but it still went through the pressing process
- Misdirected planchets – a planchet intended for one “press” gets into the wrong one (i.e. a dime planchet gets struck by a penny die)
Many coin dealers sell error coins. The various coin grading companies also classify them. If you happen to find an error coin or planchet in your pocket change, don’t throw it away. Legitimate coin errors can be sold for top dollar. As of this writing, the photo of the NGC Certified 10c Planchet Error was sold for nearly $50. Some coin errors are sold for tens of thousands of dollars!
