How can I tell if a coin is an error?
Key Things to Examine
Start by checking the coin's overall shape and design placement. An off-center strike will have part of the design missing and a plain crescent on one side. A broadstrike will be wider than normal and often thinner, with no reeded edge. Wrong planchet errors are usually the wrong color or weight for the denomination.
Use a 10x magnifier to look for doubled or misplaced elements. Raised areas that shouldn't be there (like extra letters or numbers) can indicate a die error. Also check the edge: a missing clad layer or a smooth edge on a reeded coin can be an error. Remember that many oddities are just damage or wear.
- Check for off-center design or missing design elements.
- Weigh and measure the coin; wrong planchet errors are often off-spec.
- Look for doubled features with a magnifier.
- Examine the edge for smoothness or missing layers.
Research and Verification
Once you spot a potential error, compare it to known examples on sites like Error-Ref.com or the CONECA website. These resources have photos and descriptions of many error types. You can also post clear photos on coin forums where experienced collectors can help identify it.
If the coin seems significant, consider sending it to a third-party grading service that attributes errors, like ANACS or NGC. They will certify it as a specific error if genuine. But for minor anomalies, that may not be cost-effective.
- Use Error-Ref.com or CONECA for reference images.
- Ask on forums like CoinTalk or r/coins for opinions.
- Consider professional attribution for potentially valuable errors.
Common mistakes
- Mistaking post-mint damage (scratches, dents, corrosion) for a mint error.
- Assuming any coin with a slight misalignment is an error—minor misalignments are common and often not valuable.
- Not checking the weight and diameter; many errors are obvious only when compared to a normal coin.
