filled die errors are also known as missing design element errors and as strike throughs. Some errors are known by multiple names, e.g. Labels used to identify specific categories of errors may describe the cause of the error (die crack, rotated die, clipped planchet), the appearance of the coin (wavy steps, trails, missing element) or other factors (mule, cud, brockage). For example, design elements may be missing from coins because die crevices were filled with grease - a problem with the die but the error occurs when the coin is struck. Some errors have multiple causes and not all errors fall neatly within the categories. mints, Philadelphia, Denver, and San Francisco. The planchet, die, and striking (or PDS) classification system happens to correspond with the mintmarks of the three largest U.S. Įrrors can be the result of defective planchets, defective dies or the result of mistakes made during striking. Some coin collectors specialize in error coins.

Error coins may be of value to collectors depending on the rarity and condition. Damage occurring later (post-mint damage) may sometime resemble true mint errors. Modern production methods eliminate many errors and automated counters are effective at removing error coins. However, some are inadvertently released into circulation. Coins are inspected during production and errors are typically caught. Mint error coins can be the result of deterioration of the minting equipment, accidents or malfunctions during the minting process, or interventions by mint personnel.

Mint-made errors occur when coins are made incorrectly at the mint, including anything that happens to the coin up until the completion of the minting process.

19421 mercury dime overdate