Error coins, such as those with misprinted designs or incorrect inscriptions, can become highly valuable to collectors. For instance, state quarters with missing or doubled elements in the design are rare and sought after due to their uniqueness.
Coins that are struck off-center, meaning the design is misaligned, are considered collectible. These flaws occur when the coin is not properly centered during the minting process, creating a distinct and irregular appearance that appeals to enthusiasts.
Double strikes occur when a coin is struck twice by the minting press, resulting in overlapping designs. This flaw is relatively rare and can significantly increase a quarter's value, especially if the double strike is pronounced.
Die cracks appear as lines or breaks on the surface of the coin, caused by wear or damage to the minting die. These imperfections can be interesting to collectors, especially if they create unique patterns or affect the coin's design in noticeable ways.
Planchet errors occur when the coin blank (planchet) has defects before being struck. This can include uneven edges, missing sections, or other anomalies that result in a flawed coin. Planchet errors can be valuable due to their rarity and the manufacturing issues they represent.
Minting overlaps happen when a coin is struck while another coin or debris is present on the die, causing parts of the design to be overlaid or distorted. These overlaps are relatively rare and can enhance a coin's value as a unique collectible.
Clipped planchets occur when a coin blank is not properly cut from the metal strip, leading to irregular edges or missing sections of the design. These coins are highly collectible due to their distinctive and uncommon appearance, often commanding higher values among numismatists.